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Disguises are unique. Make one pokemon look like another without changing any of the outline shape (Changing its colour to any except transparent is fine).
In essence, this is an extended recolour, where you attempt to make 1 pokémon look like another.
I don't believe so. A disguise is correct if the outline hasn't been changed. Since the ear is within the outline, you should be fine. Basicly, make sure that the sillhouette doesn't change.