I was at “The Favourite” test screening on Thursday in LA, and I can confirm that, in addition to a couple of very slight sideboob glimpses, there is one shot of Emma Stone topless in bed with one full breast clearly exposed. The scene came after I was convinced all we were going to get was the slight sideboob, so it was a pleasant surprise. I can’t swear there’s no CGI involved (although I don’t have any reason to suspect there was), but it’s a shot with the head and body in the same frame, so it’s not a double.
Thanks to “testing123” who posted the above in the comments section. We did some digging and all seems to check out. There was a test screening at The Landmark last Thursday. Another source confirms there is a scene with Emma Stone in bed with an exposed breast. This takes place shortly after a scene where Emma pleasures Olivia Colman under a blanket. The Favourite is playing in Venice and Telluride in the fall so we’ll probably get more confirmations then.