7971187
So to pick at the new stuff I'm seeing, we have Jason Voorhees, Agent Smith, some new costumes I assume (I don't play the game), a Game of Thrones stage and... aw jeez, the Teen Titans Go tower as another stage. I can only speculate that a Go character will be making an appearance from this evidence.

7971253
Or just use the area as a stage. I mean I thought the Warner Brothers and Sister would be new fighters

7971448
I think they might still be fighters. They were teasing at the end with a few more glowing forms appearing like they were implying a few more were coming. And unlike Joker, Jason, and Smith, characters like PPGs and the Warners aren't considered to be villains, so they might be avoiding to reveal their entire hand to stay with the theme.