Quote Originally Posted by Ayen View Post
In theory yes, though I'm not sure how likely it is that the CW and Fox would work together on a crossover. Supergirl is more doable because it's made by the same people as Flash and Arrow, and CBS owns half of the CW anyway.

They were able to throw Constantine in there because his show was already cancelled and by that point NBC didn't give two trouts.

Stranger things have happened. Sony and Marvel are sharing Spider-Man. And Marvel Studios green lit a couple of X-Men Universe-Based TV Shows. We just need to wait for Fox to come to their senses and share the Fantastic Four Universe with Marvel Studios.