There are some slight differences between the Japanese and English versions of the Star Fox Assault.

During the briefing sequences, all of the characters show more emotions and facial expressions in the Japanese version of the game. I have a video showing the differences in Krystal’s acting on the Other Assault Videos page.

Also, during the first mission, Krystal gets shot at by the first Aparoid to appear. In the Japanese version, it is Slippy who gets shot at. The video is also on the Other Assault Videos page.