Recently I traded a Flareon for a Ditto from Mexico. I know that a Ditto from Japan or Europe influences your chances of getting a shiny, but will a Ditto that is relatively close to where you life have an impact. (I live in the U.S)
Yes, it will.
>The key to using the Masuda method is not to breed any two Pokémon, but to breed two Pokémon created in games of different countries. -Bulbepedia
Since Mexico is a different country, the Masuda Method will work
Hope This Helped :D