I don't think the costume is the problem, it's the people. But a few do stick out as top tier troublemakers.
Deadpool and Spiderman
Because these characters are masked, they allow for anonymity. Coupled with people watching P Diddy's videos and trying to imitate his behavior without realizing that what he does is consensual skits.
D.Va and Harley Quinn
Worn by thots that want attention but don't want to put in any effort.