Ooh, this is interesting.
The thing is, the powers in Charlotte are governed by laws different from that of Rewrite. (spoilers on the two series) Iirc, in Charlotte, the charactersâ powers are latent abilities awakened by something that the Charlotte comet brought down to Earth. In Rewrite, the powers manifest as varying forms of manipulating aurora, and whether it manifests as summoning familiars or using an ability depends on what kind of âchangeâ an individual desires.
Because of that, itâs unlikely for Yuuâs powers to affect Kotarou, so I bet on our dear self-rewriting boy. I could be wrong though.