>>6040689From the wiki again:
-Megaempress notes that Shockwave's current whereabouts are unknown, referring to his disappearance from the cartoon after The Transformers: The Movie. The concurrently published Legends comics do feature Shockwave traveling to the Legends Universe, but it's currently unknown if that Shockwave is from this time period. (Characters who jump into the Legends universe seem to arrive and leave at their own time periods, while events in the Legends universe keep going at their own pace, regardless of the standard Transformers universe).
-Lunaclub refers to Starscream's ability to possess other Transformers as a ghost.
Optimus Prime's return is only temporary since he has to be dead again in time for Return of Convoy.