I never really understand what is Final Fantasy USA Mystic Quest. Why « USA » in the title ? Why Mystic Quest ?
In fact, when Final Fantasy V was released, Square think about an american released. But the game was judged too difficult for foreign teritory, so it never came out of Japan. Instead, Square developped Mystic Quest, a easier RPG think for younger gamer. Mystic Quest use many Final Fantasy code, as crystal quest for example.
So it was released first on US (1992) and then in Japan, on September 10, 1993. « USA » stay in the title in reference to the direction keep during the development.
To me, we could find US origin on artworks.