So I went ahead and did a write-up of an artifact and it's evocations. Probably overpowered but it is a 5 dot. Feedback would be appreciated, but please be kind. Also I suck at naming things but I gave it my best shot.

Here we go.

Efficacious Flow (⬤⬤⬤⬤⬤ Orichalcum Wrackstaff)
This artifact does not yet have a legend. It is six feet of orichalcum inlaid with lightning-struck copper and sorcerous obsidian that was then quenched in the freely given blood of a war god. It was forged by a young Twilight to be both the best defensive weapon imaginable and the most perfect conductor for the Essence she could feel flowing through every object and action in Creation. Despite its youth, Efficacious Flow already bears a nacreous sheen from the essence channeled through it.

Efficacious Flow possesses three hearthstone sockets, one at the staff’s midpoint and the others three quarters of the way to its ends.

Efficacious Flow is a sorcerous relic and as such may be used to initiate into sorcery and be used to create shaping rituals and merits.

Attunement: 5m
Type: Medium (+3 ACC, +12 DMG, +1 DEF, OVW 4)
Tags: Bashing, Melee, Reaching
Hearthstone slot(s): 3
Era: Return of the Solar Exalted

Evocations:

Efficacious Flow possesses an internal essence reservoir capable of holding 6 motes. When an attack is successfully blocked with Efficacious Flow, it gains one mote. If the blocked attack was empowered by charms or evocations, it gains one additional mote for each such modifier. Should the attack be composed entirely of essence (such as most spells, Glorious Solar Saber, an Implosion Bow’s blast, etc.) it gains (Attacker’s Essence) extra motes. Such attacks will be referred to as ‘Essence Attacks’ for ease of use with later evocations.

The wielder of Efficacious Flow may reflexively spend these motes to increase its defense rating for an instant, the staff seeming to twirl itself in their hands as it leaps to intercept incoming blows, trailing flags of essence in its wake. Up to three motes may be spent this way at a time. They may also be spent to fuel Efficacious Flow’s evocations. Doing so does not increase the strength of the wielder’s Anima Banner.

REVOLVING COUNTER-STRIKE
Cost: 3m; Mins: Essence 1
Type: Reflexive
Keywords: Counterattack, Withering-Only, Resonant
Duration: Instant
Prerequisites: None

When an attack is blocked with one end of Efficacious Flow, the other may twirl around to strike at the attacker and force them back. This functions as a Withering Melee Counterattack with bonus on the attack equal to the amount by which the wielder’s Parry exceeded the original attacker’s successes.

Resonant: Motes gained from the initial block may be spent toward this evocation even if Efficacious Flow’s essence reservoir is full.

SPELL CONDUCTOR
Cost: 1m ; Mins: Essence 1
Type: Supplemental
Keywords: Resonant
Duration: Instant
Prerequisites: Terrestrial Circle Sorcery

If the player stunts casting a spell in a way that uses Efficacious Flow, then they may add its accuracy bonus to the attack roll. These are non-charm dice.

Resonant: Characters resonant with orichalcum do not need to spend the 1m to activate this evocation.

Special activation rules: As long as the wielder isn’t dissonant with orichalcum, this Evocation awakens at no cost when casting an attack spell while Efficacious Flow’s essence reservoir is full.

SORCERER’S DEFENSIVE STANCE
Cost: 4m; Mins: Essence 1
Type: Supplemental
Keywords: Dissonant, Resonant
Duration: Instant
Prerequisites: Spell Conductor

Efficacious Flow gathers Sorcerous Motes through the motions of its wielder's defensive katas. She may use this Evocation to flurry a Full Defense with a Shape Sorcery action (Exalted, p. 465).

Dissonant: Characters dissonant with orichalcum cannot awaken this Evocation.

Resonant: The wielder ignores the usual flurry penalties.

GEOMANTIC RESERVOIR EXPANSION
Cost: --; Mins: Essence 2
Type: Permanent
Keywords: None
Duration: Permanent
Prerequisites: None

When all three of Efficacious Flow’s hearthstone sockets are filled, it can awake to its true potential. Its essence reservoir expands to 6*(Sum of hearthstone ratings/2). Once this evocation is awakened, inset hearthstones no longer increase their owner’s essence regeneration. Instead the motes they would restore are fed into Efficacious Flow’s reservoir. Inset hearthstones still provide their other benefits.

If the wielder lacks three hearthstones, she may instead fill an empty socket with a geomanticly faceted gemstone (resource cost ⬤⬤⬤⬤) that is calculated as being a one dot hearthstone for the purposes of how much it expands Efficacious Flow’s reservoir.

FORCEFUL PROJECTION
Cost: 2m + 1m per die; Mins: Essence 2
Type: Supplemental
Keywords: Resonant
Duration: Instant
Prerequisites: Spell Conductor

By tapping into Efficacious Flow’s reservoir and projecting her will out through it, the wielder’s mystic actions pack that much more punch. Motes may be spent from Efficacious Flow to pay for the wielder’s Occult Excellency. Normal dice limits apply.

Resonant: Characters resonant with orichalcum do not need to pay the 2m surcharge to use this evocation.

TWISTED RECOIL
Cost: 3m (+1wp); Mins: Essence 3
Type: Supplemental
Keywords: Resonant
Duration: Permanent/Instant
Prerequisites: Spell Conductor, Celestial Circle Sorcery

This evocation permanently enhances the Counterspell action, any motes drained from a spell are added to Efficacious Flow’s reservoir. However by paying a willpower, those motes may be sent right back out to smash apart the remaining structure of the spell, resulting in twice as many motes lost.

For three motes, this evocation can also be used to extend the range of a Countermagic or Distortion action out to medium.

Resonant: If the wielder is both resonant with orichalcum and knows the Sorcerer's Defensive Stance evocation then they may pay its cost to flurry a Full Defense with their Counter or Distortion roll. This flurry is made without the usual penalty.

POWER SINK
Cost: 7m, 1wp; Mins: Essence 3
Type: Reflexive
Keywords: Dissonant, Resonant, Clash, Dual
Duration: Instant
Prerequisites: Revolving Counter-Strike, Geomantic Reservoir Expansion

Efficacious Flow forgoes its normal method of leaching away a few motes from blocked strikes and absorbs the entire force of an attacker’s blow, pouring the energy back into the Manses of its inset hearthstones. On a successful block, the attacker feels as though they have just struck the immovable Pole of Earth, and with just as much effect.

For Decisive strikes this means that even though their attack was unsuccessful, the attacker still resets to base initiative.

For Withering attacks, the attacker rolls their damage pool plus the number by which the defender’s parry exceeded their attack. They lose initiative equal to the number of successes on the roll.

If Efficacious Flow is using gemstones instead of hearthstones, its wielder must roll (Intelligence+Occult) against a difficulty of (Attacker’s Damage Pool / 3, round up) for each gem. On a failure, the gem shatters causing one level of lethal damage to the wielder and Efficacious Flow’s expanded reservoir collapses in a bright flash of colorful but harmless light. It returns to its default 6 mote pool until the socket is filled again.

Dissonant: Characters dissonant with orichalcum cannot awaken this Evocation.

Resonant: A character resonant with orichalcum may help Efficacious Flow hold onto some of the energy pouring through it. For every two initiative that the attacker loses, Efficacious Flow gains one mote, up to a limit of (Wielder’s Essence + 2).

WELLSPRING OF MOTION
Cost: 1wp + 2m per 1i; Mins: Essence 4
Type: Simple
Keywords: Resonant
Duration: Instant
Prerequisites: Revolving Counter-Strike

Resonant: Only characters who are resonant with orichalcum may awaken this evocation.

Just as Efficacious Flow may sap the force of blocked attacks and use it to enhance its own motion, so too may the wielder once they have grown attuned to the artifact. They may spend a willpower to tap into Efficacious Flow’s reservoir and blur into motion, repositioning themselves for the greatest advantage. For each five initiative they gain this way, they may also chose to move one range band uncontested. They are still limited to their normal locomotion, just blindingly fast, so this does not allow them to climb walls or cross chasms that they could not naturally overcome.

ESSENCE CONDUIT
Cost: 3m, 6m, or 10m, 1wp; Mins: Essence 4
Type: Reflexive
Keywords: Counterattack
Duration: Instant
Prerequisites: Twisted Recoil, Power Sink

Expanding on the principles of Power Sink, Essence Conduit allows Efficacious Flow to absorb the entire force of an Essence Attack by foregoing draining motes from it. This confers three benefits:

For 3 motes, Essence Attacks that are normally unblockable attacks may be blocked by this charm.

For 6 motes, Essence Attacks that are blocked that would normally continue into subsequent turns are immediately ended as the effect is drawn up into Efficacious Flow.

For 10 motes and a willpower, rather than grounding out the energy of the attack into Efficacious Flow’s connected Manses, it flows as a glowing wave of light from one end of the wrackstaff to the other, where it is emitted in its original form under the wielder’s control. The Essence Attack is directed by making an (Intelligence or Dexterity + Occult) roll that may benefit from Spell Conductor even if the Essence Attack was a charm rather than a spell. The strength of the Essence Attack remains the same as when it was originally cast, using the same dice pool. If the Essence Attack can be maintained, any committed motes may be paid from Efficacious Flow’s reservoir should the wielder so choose. If the Essence Attack is a Solar Circle spell, it may be redirected but not maintained unless the wielder is also initiated into Solar Circle Sorcery.

SPELL TRAP
Cost 1wp + 1m per 5sm; Mins: Essence 5
Type: Reflexive
Keywords: Reflexive
Duration: Indefinite
Prerequisites: Solar Circle Sorcery, Essence Conduit

When casting a spell, after the final Shape Sorcery action has been completed but before it takes effect, Efficacious Flow’s wielder may thrust it into the spell matrix absorbing it as with Essence Conduit. As the light of the spells energy travels down the staff, the wielder may pay a willpower and commit one mote per 5 sorcerous motes in the spell rounded up (these motes must be paid from Efficacious Flow’s reservoir). This makes the inlaid copper and obsidian glow and liquefy. The moment before the spell would leave the staff, the flowing metal and stone shape themselves into a glyph representing the spell and snap back into solid form, trapping the spell for as long as Efficacious Flow’s motes remain committed. Releasing the commitment is a simple type combat action.

Capturing their own spell in this way prevents the wielder from seeing their shaping efforts come to fruition and denies them regaining the usual point of willpower from successfully casting a spell. This evocation may also be used to capture Essence Attacks absorbed with Essence Conduit.
Up to (number of hearthstones) spells may be trapped in Efficacious Flow at one time if the wielder is willing to keep the motes committed. Only one spell may be released at a time. For each spell, one of the connected Manses is suffused with cosmetic effects evocative of that spell’s control effect until it is released.

Removing a hearthstone or shattering an inset geomantic gemstone while spells are held in this way is catastrophic. The half-shaped energy bursting forth as Efficacious Flow’s reservoir collapses causes uncountable recurring damage to everyone in short range of Efficacious Flow for a number of rounds equal to the sum of the Circle of each spell held (for example if a Solar and two Celestial spells are held 3+2+2=7 rounds). This breaks Efficacious Flow and all three stones.