Different suggestion: could we believably dub Rey to say “No” during one of her mouth movements, cutting out her “and I?” Here’s what I’m thinking for the scene:

Palpatine: “I am all the sith! A scavenger girl is no match for the power in me! You are nothing!”

Rey: “No.” catches lightsaber “I am a Jedi.”

If the whole trilogy is Rey dealing with where she belongs, whether or not she’s a nobody, rejecting her dark heritage, and ultimately embracing her place in the Jedi/Skywalker legacy, this ordering/dubbing of dialog might make for a better finale for her arc. And it further reduces the Avengers Endgame comparison that we were already kinda trying to do.