Yea, there's a leaked picture of his appearance in the character selection screen
Also, apparently different costumes and skins will give characters different voices, dialogues, winning animations and starting animations. Like in the superman video above, he appears villainy because I think he serves as an antagonist in the game (he creates a new world order after joker kills Lois lane, along with millions of other people).
But if he uses his original costume, his winning and starting animation appear heroic.
The batman fight vs wonder woman was perfectly put together. Batman had to use the environment to win, and when he attacks WW head on, he gets his butt kicked.
I think batmans super could be better. I prefer that he throws a smoke bomb at his enemy, making the enemy confused, then the batmobile appears out of nowhere and sends the enemy to the ground. And while the enemy lays on the ground, the smoke begins to clear out and you see batman storming down with the batwing, shooting his cannon and rockets, and then ejecting to crash the plane at the enemy. I think that would've been better