I'm honestly not sure. I would love him in MCU!Loki's helmet and having him have fun with shape-shifting, but Robin Hood!Ren would be solid too. Especially since it wouldn't be that much different than being a Phantom Thief.

Yeah it would. Ren is from 20XX I headcanon it as 2016 myself so it's possible he might know that he killed people, though we could play it out as him not having heard about it if you don't want Ren to know ICly.