Well the generation isn't exactly done yet. By the end MHW would probably inch over 12 million, GT Sport will get over 5 million, FF15 will probably get to at least 8.5 million, and RE7 could get to 6 million. The 3M figure for Nier was before the Xbox version, so 3.5 million will come easy. Dragonball Fighterz is selling well and will probably get it's own spot in that list.
Plus Kingdom Hearts 3 and Sekiro are coming.
Bet with Intrinsic:
The Switch will outsell 3DS (based on VGchartz numbers), according to me, while Intrinsic thinks the opposite will hold true. One month avatar control for the loser's avatar.