Seeing as its another distant region from the previous five, I don't see there being any story continuation from any of the other games. Possibly a few nods here and there to acknowledge past events from another region, but no real plot tie-ins from other games. It's a new region with new people and new villains. It should have its own story.
The only real way a continuation of plot can work is if it's a sequel or a la RBY > GSC.
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