Unfortunately, Ditto's ability has no effect on the chances of breeding HA mon.
And the Masuda Method does not increase in chance of both mons are from two entirely different foreign regions, if I remember correctly, it will just be the normal Masuda Method rate. Remember that the parents have to be different: for example, two JPN mon will not make the Masuda Method work but a GER mother and a JPN father will.
Breeding for specific Hidden Power is a whole different ball game, you have to nail an exact combination of IVs.
This page explains it well. It is a little outdated, since Hidden Power will always be 60 power in this gen but it's a good reference.