Thanks Misaki, I think I've watched that before but I'll check it again.
Nate, in my games there's only a single json sprite/skeleton chosen to draw per character object, depending on their direction, as shown in the Create Event screenshot. Above the VS is the single skeleton/json sprite assignment and below the VS are the multi-skeleton/json sprite assignments, which are what I'm going to switch back to trying. Do you know of any issue doing this?
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I'm not sure about trying to combine multiple jsons for a single character... sounds like a multi-headed hydra type boss or something lol.
I'll let you know if I see any visual issues (i.e. animation jumps when the json sprite changes), but from what I remember when I first tried it, the animations blended fine when changing from json to json as direction changed.