As we can read on giantbomb.com, FX Fighter is a cancelled fighting game, used to promote the PC-FX and it’s graphical capabilities. A demo was shown at the Tokyo Toy Show in 1994. The game was a 1-on-1 3D fighter which used FMV to represent the characters movement. The game was cancelled halfway through development with only 3 or 4 characters done because the sheer size of the FMVs needed to complete the game exceeded the capacity of a single CD.
Thanks to Celine for the contribution!