What could it (they?) be?

Capcom will have at least one unannounced title playable at Jump Festa 2020, which runs from December 21 to 22 at the Makuhari Messe in Chiba, Japan.

The company’s booth will have a total of four playable titles. The currently confirmed lineup of playable titles include:

Mega Man Zero/ZX Legacy Collection (PS4, Xbox One, Switch, PC)

Monster Hunter World: Iceborne (PS4)

Thanks, Ryokutya2089.

Update 12/02/19 at 8:50 a.m.: Street Fighter V: Champion Edition has been confirmed as one of the four titles playable at the Capcom booth, leaving only one more title to be confirmed.