Subversigender is an antigender that is subversive, anarchistic and anti-establishment. It is a form of rebellion against traditional gender ideals. A subversigender individual feels like they will never conform to a "normal" or "expected" gender, and they prefer to present as shocking as possible. They may view their own gender(s) and gender in general with anger, disgust and contempt.
And you would like a pride flag for Subversigender?
(Sorry if you asked that, it got eaten up if you did)
It sounds similar to Genderpunk, Genderfuck, or Gendermaverick. It does sound different enough, though, especially due to that last sentence about how “They may view their own gender(s) and gender in general with anger, disgust and contempt”.
Sure, we can make a flag for your gender. :)