Is it odd for one surgeon to do both mastectomies and FFS? I'm not at all sure it sounds like a good idea.
It would be very unusual these days for a surgeon to do mastectomies for cancer as well as facial surgery, but plastic surgeons do do breast reconstructions. Removing non-cancerous breast tissue is probably within a plastic surgeon's skill-set, as it's not really that different from other forms of plastic surgery. So I wouldn't say this is a huge red flag, though I'm not a surgeon - surgeons might disagree.
I would say that live-streaming your ops, even with full consent and if you're the best surgeon on Earth, is asking to be sued. * *