A tweet has just revealed the two veterans to the series, Captain America and Morrigan. Here is the tweet containing the trailer:
It seems like the infinity stones will be the X-Factor of MvCI. It also seems like the infinity stones will act as some sort of assist from previous games. Although this is pure speculation from not seeing any traditional assists used in either trailers.
This unfortunately does nothing to confirm if there will be any x-men characters like Wolverine and Storm, both of which are popular staples to the fighting game franchise. It is rumored that this title will not be featuring any mutants due to Marvel not having the rights to X-men, Fantastic Four, Spider-man, or Deadpool. Although Captain America: Civil War featured a young Spider-man, so I’m not really sure whats going on there.