In both settings, there’s sort of a frontier tension to that too.
Ostromarka is about being on the edge of civilisation with only demonic wasteland and death beyond. Some of that old gods worship is potentially corrupted by things in the Wastes, some of it is just a reaction to the Imperial Edicts handed out back in the capital to the west.
In Out West, that tension is probably more about the way worship happens, though the Old Gods could just as easily be the way the local tribes worship too. There’s probably also a sort of resurgence in the old ways following the fall of the Liches back east, but maybe people don’t agree on how the old ways were.
Either way, I think those conflicts should be a part of the settings.
It’s odd that they’re East and West, right?