Everything seems to indicate that ‘Avengers: Endgame’, was not the last appearance of the Crazy Titan that we will see in the Marvel Cinematic Universe (MCU), since if the rumors of Marvel are true, Nova will return to Thanos to the MCU.
According to rumors, Nova, could debut in phase 5 of the MCU, and would do so with a movie of origin, as was the case with Captain America and Captain Marvel, so we could see how Richard Rider, became The Man Called Not going.
If this script is followed, we would witness how Richard inherits the power of the Nova Corps, while his home, the planet Xandar, is destroyed, in this situation Richard absorbs the Xandarian Worldmind, to protect it and guarantee its existence.
RELATEDSource: Marvel Comics
Now, if in the comics, Thanos is not responsible for the destruction of this planet, in the MCU it is, since Thor explains that the Crazy Titan got the gem of power, when he destroyed Xandar, so this powerful Villain could return to this universe through the history of Nova.
One of the strengths for this to come true is that many MCU fans don't know Nova's story, so an original movie could be a very good decision and more if it is backed by a villain with fame Thanos, so this would attract many people to movie theaters.
And it is that the character has always been hovering in the mind of Kevin Feige, so he declared in 2017 for ComicBook. “If we have a large board with a lot of characters that have a more immediate potential, Nova is on that board, due to the connection with the Guardian universe, because there is more than one example to get out of the comics that are interesting and You're absolutely right, he was in the first drafts of 'Guardians of the Galaxy'. ”
So it is possible that the character first appears by means of a cameo in some Marvel movie, to later have his own original movie, in which, Nova will return Thanos to the MCU.