At the person who flagged this:
The uploader wasn't able to find the parent post under "Similar".
You could use the toolbar at left where you can find "Find Similar" or use "Edit" and click similar there.
Also: The colors are slightly different. For example the PokéBall t the right upper corner. So I'd say that it could still be approved.

And Team Skull is not a character, it is a team.
So the corresponding cosplay tag should go to team_skull_grunt and not to team_skull.