Here's some other circumstantial evidence for Injustice 2:
A quote from Geoff Johns on being promoted as well as remaining Chief Creative Officer where he mentions present involvement with Netherrealm and character choices:
"My job is to help other Warner Brothers divisions work with DC. I work with Warner TV and producers to get these shows up and running, in particular with
The Flash, where I co-created the show, wrote a few episodes, wrote the pilot episode," Johns said. "I work with other people, Ames Kirshen in games,
the studios like Rocksteady and Netherrealm, go in there on character choices, story they’re going to do and brainstorm on that, try to keep it true to comics."