During development Hayate's "Heat Haze Vortex Climax" was simply called 'UFO', before it was finally given a proper name.

Hayate was removed from the arcade roster of EX2 Plus for unknown reasons, making a previously unlockable character, Nanase, a normal character in his stead. Hayate was added back in the home port of the game, but as a secret character.

In the Japanese version of Street Fighter EX2 Plus, blood effects were shown whenever a character was attacked. This was removed from international versions.