I think that a lot of people who didn't buy last year's disappointing COD, will buy the new one now. I think the PS4 version can reach 12M, just like Mario Odyssey.
Assuming that SMO will generaly be considered to be a very good game, and the new COD to be mediocre, I think it's slightly more likely that Mario will win lifetime.
COD will probably win year one and pre-orders.