Found this article by Cooper Hood at screenrant.com.  The headline pretty much says it all:

Chris Hemsworth Claims it is “Illegal” for MCU actors to take DC Roles

Now, Mr. Hemsworth, it should be noted, said this in a panel at a comic book convention and, perhaps, he was being quite tongue in cheek about the statement.  I mean, “illegal”?  Like… he can be arrested for appearing in a DC universe movie?

I certainly don’t think so, though I could see the powers that be at Disney/Marvel frowning very heavily at the idea that someone as well known for a role as prominent as he plays in the MCU suddenly appearing in an equally big role in a DC movie.  I mean, should he appear in civilian attire as a small character in a DC universe film I guess it might be ok, but what if he should appear in the role of, say, a Booster Gold?

Granted, the character isn’t as big as a Batman or Superman or Wonder Woman, but he’s big enough and the character, as presented in the comics, does have the look of Mr. Hemsworth.  There are other possibilities, too.  How about the Phantom Stranger…?

What if they decide to make a Green Arrow movie that, like the Flash in the movie universe, isn’t tied into the TV show?  Mr. Hemsworth could certainly look the part…

Anyway…random speculation on my part.

Still, who could one see Robert Downey Jr. play if he were to appear in the DC movies…?

Could he make an interesting Blue Beetle to Chris Hemsworth’s Booster Gold…?

I don’t know…it might just work…