Arc System Works have announced a new fighter that will bring together characters from different properties. The fighting game itself is called BlazBlue Cross Tag Battle and will feature characters from the BlazBlue series, but you also have Yu from Persona 4 Arena, Ruby from RWBY, and Hyde from Under Night: In Birth. The game is expected in 2018 and platforms are yet to be confirmed. You can check out the game in action below.
Source: Press Release