My guess is that the voices are left in the original language and only the
text is translated in undubbed version. (same as in normal movies with subs)
There shouldn't be any difference in gameplay unless
something was cut off from the original scenario or the scenario was
americanized. (same like in manga when they change parts of the storyline
to apply more for the local audience).
Sometimes original voices are way better than the dubbed ones.
Hope you understand what I had in mind.
