Hey why not
The other side will be making a opposite version of the other cross over game, with completely unique gameplay.
"Along with Street Fighter X Tekken, we're going to get Tekken X Street Fighter... a completely different game, developed be Tekken's developers.... so this really is a battle! Sweeet!"
READ THIS:
Street Fighter Cross Tekken will be done in SFIV visual style with Street Fighter 2D gameplay.
Tekken Cross Street Fighter will be done in Tekken visual style with Tekken 3D gameplay.