A couple observations:
- The youngest member of the Bonne family, Bon Bonne, can be seen floating in the water wearing his inner tube from the ending of Mega Man Legends 1.
- Looks like our previous speculations were right: Teisel and Tron are sitting on top of the Balcon Gelede mech.
- In the third screen, you can see the Gesselschaft flying by in the background.
- The tower in the background is definitely the first Ruins from MML1, although I don't remember it being that close to Cattelox.
- Third screen, there's a poster of Tron hanging off the side of a wall.
- Servbots are holding flares or something.
Again, because Tron is a background character here, her chances of being playable are slim. Traditionally, background characters in Capcom fighting games are usually limited to cameos and not necessarily playable.