Not manga, but Squaresoft released Final Fantasy Unlimited, an anime series back in 2001. There was also Final Fantasy: Legend of the Crystals. It was a four part series. It follows the Final Fantasy idea well, but Nobuo Uematsu had nothing to do with this anime. It was FF by name only.

FFU is a more underground series, this is probably what your friend was referring to. Manga and Anime are commonly switched terms since most Americans and Europeans don't know the difference.