Anna's Spell Transposition

You choose to become a conduit of magic for the creature. You grant them access to your prepared spell list, and they can choose to cast a spell using your spell slot, but cannot cast a spell higher than 5th level.
They use your spell attack modifier and spell save DC, but are treated as the caster for all other purposes, such as concentration and material components for the spell they cast.
At Higher Levels: If you cast this spell using a spell slot of 7th level or higher, the spell level that they can cast through you increases by one level for each spell's level above 6th.