There are several VKs, so maybe there's someone who doesn't like the idea of "being good" and acts as the main antagonist.
There are also those who theorize that Pink could be an antagonist, a girl who doesn't really like being good, like her mother is in the new timeline. (Which would continue the message of the franchise that it doesn't matter if your father is considered a Hero or a Villain; children can be the opposite of their parents, as seen with characters like the Core Four, Red, Audrey, Chad...)
Or maybe there's some other new character, or a character from the Disney Classics who acts as the main antagonist. I guess we'll have to wait to find out more about the plot...
