Archetype!reader

Counterpart!reader

The user is someone who looks like another character, preferably, but not limited to the main character or hero.

While the counterpart may cause trouble for the one they look like, they are not always evil. Aside from being rivals or villains, they could be anti-heroes, good people or maybe even heroes. The look-alike may have some or all of the other character's abilities, or they may have some of their own. They may also have some differences, and could even have some opposites to the character they look like, but still have a lot of similarities and things in common with the character.

https://powerlisting.fandom.com/wiki/Archetype:Counterpart