Many Star Wars fans were upset when Disney canned the expanded universe upon taking over control of Lucasfilm. However, the "Legends" stories, as they're now known, have seen bits and pieces reintroduced into canon over the last few years and it appears that is going to continue to happen over the next several months. Leland Chee, a member of the Star Wars Story team recently responded to a fan on Twitter who asked if some expanded universe characters might be reintroduced into the franchise, by confirming that it will be happening. According to Chee...
For decades in between the original trilogy and the prequels, Star Wars fans only had novels, comic books, and video games to keep them involved in the franchise. This material created hundreds of new characters and plot lines that were all eliminated when Disney took over. However, it's been obvious from the beginning that while all the old stuff may not be considered canon, it was still having an influence on the new Star Wars stories. Han Solo and Leia had a son who went to the dark side in the movies, just as they had previously in novels. Luke Skywalker went on to train a new batch of Jedi as well, though details went differently in each case.
Things changed in a big way, however, when Grand Admiral Thrawn, the big bad from the very first Star Wars novels, the Heir to the Empire trilogy, was introduced as a character on the Star Wars Rebels animated series. That made it clear that characters that had been created entirely in the old expanded universe could see new life in the current canonical universe. Leland Chee now confirms we'll see more of that, though he's quiet on details.
Chee makes a reference to Tag and Bink, a pair of characters who were introduced in an old limited comic book series who we know we will be seeing later this year in Solo: A Star Wars Story. While we have no idea how big a role they will have at this point, as Leland Chee says, if a pair of purely comic relief characters are being added to the Star Wars universe, anything else is possible.
Of course, the sheer size of the expanded universe, and the fact that Star Wars exists in every conceivable form of media, means that the possibilities are nearly endless for how these characters could be introduced. Will we see other Legends characters in Solo\_: A Star Wars Story_ beyond Tag and Bink? Could other characters show up in novels, comic books or on television? The permutations are considerable.
If it's happening over the next few months then we're likely looking at Solo or the last season of Rebels for the visual media options. However, even if your favorite character doesn't appear soon, the fact is that if Lucasfilm is mining the Legends universe for material now, they'll likely continue to do so for years to come, and the character you love could still appear someplace down the line.