I'll drop a line of interest.

Would an alien traveler whose ship either crashed/got shot down and/or lost her memories(and thus forgot how to use her powers due to her species rules work), be considered viable? Actually...that might be too much.

Might just do a genius who's akin to, mm, I dunno. I like playing with "tech-based" stuff. Could be genius who has to live inside a protective environment, due to a weakened immune system, or something?
Could alternatively do an alien from another dimension whose powers barely work due to being "severed" from the source of his kind's power. Would be adapting an RF OC of mine, if you know the series. And is a kid. Probably lost some of his memories too. If that don't work, I gotcha.

I'm just tossing out ideas here, since it sounds fun.