Change

User can permanently copy any quirk however they can only use one at a time.

In order to copy a quirk the user must spend a significant amount of time near them or be near the user when they use their quirk.

It works faster on mutation quirks and slower on emitter quirks, transformation quirks are in between the two on time.

It takes a few seconds for the user of change to swap quirks and repeated use can cause fatigue but with training they can do it a bit faster.

Their plus ultra move would be temporarily using multiple quirks at the same time by rapidly switching making them stack on top of one another but be at full power in bursts as the quirks would be transitioning out.