I recently discovered the new infernocus toy which came with a small Quintessa figure, while I was going through responses some people said they would've preferred infernocus was Unicron however when you think about it Quintessa is Unicron, she is the movie version of Unicron. I mean think about it, Quintessa likely is the giant planet and serves as it's core. The giant planet looks like it devours or assimilate other world's. Quintessa has the ability to control or corrupt other transformers which makes their eyes turn purple (dark energon). Quintessa is tied to the origins of the transformers. Quintessa's guardian looks like Unicron's robot form. This is Unicron only change the blue figure to a male and give it a different name and you have a movie version of Unicron. They likely went with a female for the king Arthur story where Quintessa will likely be the lady of the lake, which wouldn't fit Unicron. Either way for all intents and purposes Quintessa is the movie version of Unicron; she has a different motive and personality but definitely fills in pretty much the same story role and threat so there's really no reason to introduce Unicron after this movie since his threat would be way too similar to TLK, so they likely won't.