Bleeding is really just a hack to work around incorrect blending when not using premultiplied alpha (PMA). You shouldn't see black borders if your images are PMA and you enable PMA for the renderer. I just tested spineboy, exported the JSON with atlas using PMA, ran AnimationStateTest, had black borders (forgot linear in this screenshot):
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Called renderer.setPremultipliedAlpha(true) and rendering is good:
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