Will Masuda method work with Pokemon from different regions but same English name?
Short answer: Yes
According to Bulbapedia:
The Masuda method involves breeding two Pokémon created in games of different languages.
So the current Pokemon's name is not important.
You're worring for no reason, since the Spanish name for Furret is the same as the English one, as you can see here (courtesy of Bulbapedia, again):
So Australian Ditto + Spanish Furret can definitely use Masuda method.