Take This With HUGE! Shaker Of Salt.(casting rumor)

I think even with a production deal,you can still work with other studios on other stuff.Actors and filmmakers do that all the time.I think Melissa's production deal with WB is more about original content that she is developing whether she acts in it or not.WB has first rights to anything she develops with her company.For example,'The Girls On The Bus she's starring in but is also producing for WB thru her production company.’Plus,I think her deal is for television only.She can still do a movie with other studios.

With that said,yes,sigining on to the MCU in a hero role is a multi film commitment They like their leads to sign on for 6-9 films at a time because they want to use them for crossovers across the MCU.You're talking about an at least 6-10 year commitment in a lot of cases.It's hard to see Melissa sigining on for that after doing Supergirl for a little over half a decade.

What I could see a little easier is playing a villain role in the MCU.The villain roles tend to be for one movie only and playing a baddie can be fun as a one-off in a superhero project.Christian Bale spent 8 years playing Batman but signed on to play the villain,Gorr in the new Thor film.Villains tend to be one and done in most comic book movies(not all ofcourse).

Grain of salt indeed. Signing in the MCU is usually a multi move comment and I just don’t see Melissa signing up for that especially in a physically demanding role. Also she recently resigned a deal between WB and her production company, could be a conflict of interest there. On the other hand money talks and this would be quite a bit of it.