It's released the same way as regular sets, right?
Because I opened a Japanse box, still missing 3 GXs and did not get any FA, but I have opened 4 Korean boxes of other sets so far (1 was Evolutions, so different) and those usually have such bad pulls (2x GX/EX per box, which even can be the same) that opening a Japanese box is better.
I only would recommend Korean boxes for special sets, which have a fixed 1 holo/pack there but not in English and/or are not released in booster boxes in English.