Kuma's Nikyu Nikyu no mi should be especially useful against Blackbeard's Yami Yami no mi with Kuma's Air Paws and Ursus Shock being very dangerous for Teach and his ability to push himself could allow him to counter Teach's vortex to an extent by using it to escape the gravity or to deviate the trajectory.
Kuma's pain transfer technique could also be a potential mean to defeat Blackbeard by amassing the pain of many persons or several super powerful characters with epic pain tolerance and then transfer all the pain to Teach whose df causes him to feels pain in an increased way, causing him so much pain that he would lose consciousness.