Episode 12 has Ultra Magnus in it, but isn't yet known to be a QT toy.... so maybe one is coming and they are including some future toys before the 13 episode series wraps up.
Or since the QT cartoon series is just talking about the 80s Japanese computer game "Mystery of Convoy", a guest appearance of that original game character (with the other two Autobots in the game) was probably expected.

After seeing the Gen1 Convoy toy coming in April having the full (deformed) trailer like the Choro-Q Convoy toy, it should be possible to have a full trailer Ultra Magnus too... but it would have to be solid, not hollow like a car carrier.

This episode has Ultra Magnus crying a lot because the other two characters (Bumble & Rodimus) are talking and laughing about his role in the notoriously difficult 80s game, in which it was so easy to die in it (as Ultra Magnus).
The end of the clip has the QT Bumble in the 80s game, and failing.

Has anyone been able to access the Japanese QT game to play it, or is it one of those localised App deals that requires you to be of a Japanese address?