@Dhranios Regardless of how I phrased it, the core issue still remains. Do I have to create a whole new ticket?
@Dhranios Thats incorrect. The robe layers as part of the body cube and not on the (slightly larger) separate robe cube. Look at the widths. The robe on the villager is wider than its legs, but the robe is the same width as the legs on the z-villager. Look at how the top of the villager's robe collides with its head, while the z-villager's does not. The robe texture for the villager is a secondary layer that doesn't cancel out the under layer, but it does on the z-villager. I've uploaded more images; please whoever marked this as invalid, take an actual deeper look into this.
@B4dAtMC The resourcepack in picture 2&3 (which has the exact same mapping as vanilla zombie villagers) is not the cause as this occurs even in its absence (reference picture #1). Resourcepacks cannot edit entity models. Please do not lecture others about things you don't understand.