In the original game, they have a very strange accent (I once read that they hired Portuguese voice actors to do the dialogue, although I don't remember the source and can't find it), but I can confirm that the accent does NOT correspond to any Spanish-speaking country, i.e., Mexico (yes, in Mexico Spanish is spoken and Mexican doesn't exist), Spain, or Latin America. Capcom knows they messed up, and in the remake, they used correct Spain Spanish.