One problem with adapting the Thrawn Trilogy to the big screen even if the fans, Disney and Lucas wanted
to do so (which they clearly don't) we have the issue of the Zahn novels taking place only a relatively short time after the events of Return of the Jedi
and the deaths of the Emperor and Darth Vader. The new Trilogy is most likely going to be set some 30 years or thereabouts after Jedi
to account for the ages of actors like Hamill, Fisher and Ford if they indeed appear in the new movies.
The Thrawn story just doesn't work if it's set several decades later than in the books. That said, it's not happening anyways. I'd be the first SW geek to cheer if Thrawn showed up as a background character or supporting villain in one of the three new films but I'm not expecting it and I don't want any of the post-Jedi
novels adapted for the big screen.