It's very hard to tell at this point. Things are going to be much clearer in 2 years from now (by that time, possible revisions will be already out and we can understand better Switch's library and future potential).
If I had to guess right now, I would say something around 120m.
Bet with Teeqoz for 2 weeks of avatar and sig control that Super Mario Odyssey would ship more than 7m on its first 2 months. The game shipped 9.07m, so I won