My first thought is that's a good idea for a video, I'll add that to the list. My second thought is any of our dryland videos on wrist exercises and ball handling will be great for your offhand. One of them is here: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-hkgKerrCJL4.htmlsi=jMgLMbFDGtV4oXKH