Oh man, did you try tossing them in cornstarch first? That was my game changer. I leave like a full inch between pieces, like they shouldn't be touching at all, which feels like a waste of space but it works. I do small batches now and just keep the first ones warm in the oven, it takes longer but they actually get crispy. Crowding is the worst, it just steams everything.
Wow cornstarch is a solid move. @saraht77 is totally right about the crowding, it's a killer. The real secret weapon though? Letting your chicken sit out for 20 minutes before you fry it. If it's fridge-cold when it hits the oil, the temp drops and you get greasy. Room temp chicken fries up way crispier. Changed my whole game.