For what it's worth, we actually see Ezra "non-lethally" remove a trio of stormtroopers from combat in an episode of SW:Rebels (the one with the Interdictor), simply by destroying their blaster rifles and then going on to rather cheekily reply that he did promise the troopers he wouldn't hurt them. Mechanically, he pushed them over the wound threshold for the minion group, meaning they were defeated, and GM Filoni liked the description of Ezra bouncing around and slicing up their weapons instead of slicing up them.
As a GM, I'd certainly allow for the player that wanted to avoid killing their opponents to do something like that, especially if they rolled a Triumph as part of that roll.