Actually, that could be a good reason Fairy type exists in Kalos in the first place.
That logic doesn't work. Pokemon that live in other regions have now been retconned to being fairy-type as well.
Yes and no.... Fairy Type was created this gen. That would mean it's been discovered in the Kalos region. Aside from a remake of a previous game, they could always say that those Pokemon migrated to other regions in the years since, like Johto Pokemon appearing in Kanto in Generation 2/4.
Remember, we've so far only explored Kalos this generation. If RSE remakes come out, then it would probably be retconned.
EDIT: Oh, and they actually reference it in Black 2/White 2, how Pokemon distribution has changed drastically in the two years since the original B/W. I don't think they explained why, but they at least pointed it out.
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