The Masuda Method works by having using one parent from your local language, and another parent from a foreign language. This drastically increases the odds that any given egg from that pair will be Shiny.
In your case, I would use the foreign Ditto and the foreign Pawniard to quickly get 1 egg, hatch it, and then replace the foreign Ditto with the one you just hatched. Because you hatched it, it the child will be your local language, thereby making it the perfect partner for your foreign Pawniard under the Masuda Method.
Unless you are also IV breeding at the same time, and the Ditto has good IVs you wish to pass down. In that scenario, you should keep the foreign Ditto, and replace the foreign Pawniard instead. I have a 6 IV foreign Ditto that will forever reside in my Daycare for this express purpose.