In america, foreign pokemon in breeding will make a more incresed shiny egg; so in a foreign country, would american pokemon in breeding have a chance to be more shiny?
Depends on your version so yes I think it will.
In Generation IV, a new mechanic was added to breeding: there is now an increased chance (1/2048 as opposed to 1/8192) of hatching a shiny Pokémon when both parents are from different language games. This is due to special coding written into the game by director Junichi Masuda. Aside from this addition, the means of breeding for shininess are otherwise unchanged."
quoted from >http://bulbapedia.bulbagarden.net/wiki/Breeding