... well then. That's mildly disturbing. I would've said Spy would be Loki because they're pretty much the same (looking like different people, invisibility, thinking he can outsmart everyone, etc.) but he's already Black Widow here.
I saw this as a spray ages ago, and now I finally found it! (Btw, I do consider Nick Fury part of the Avengers team. Tony Stark, Hawkeye and Black Widow don't have actual superpowers either. Stark is a gadgeteer, while Black Widow and Hawkeye are more like Batman or Daredevil or Catwoman.)