With the aid of a friend, we went over some of the characters for FF6.

Locke = Gryffindor
Terra = Ravenclaw
Edgar and Sabin = Hufflepuff
Celes = Slytherin
Cyan = Gryffindor
Shadow = Slytherin
Gau = ...umm, out back with Hagrid?
Setzer = Slytherin
Strago and Relm = Ravenclaw

EDIT: Just heard from another friend. This one is for FFX.
Yuna = Gryffindor, most of her crew would be Hufflepuff
Auron = Gryffindor
Lulu = Ravenclaw
Seymour = Slytherin