Hard to say. Monster Hunter is a very popular franchise, no doubt, especially in Japan where it is consistently one of the top three most popular third-party series (along with Final Fantasy and Dragon Quest) and a reliable system-seller. World is by far the best-selling game in the series at 16.8M copies, but it was a multiplatform game and we have no clue what the platform split is. All we know beyond the global total is that it did well enough to make it into the Top 10 of 2018 in the U.S. (overall and for both the PS4 & XBO individually) and was the best-selling PS4 game ever in Japan. It was also the first and only entry in the series where the clear majority of sales came from outside of Japan, which is why it sold as well as it did. While previous MH games never sold over 2M copies outside of Japan, World put up outstanding numbers outside Japan. Even though it was the best-selling PS4 game ever in Japan, that's not saying much as it apparently didn't even quite hit 3M even when including digital (nowhere close to #1 in the series in Japan), which would leave at least 13M for elsewhere.
But was that global success a fluke? Would it be possible to replicate on the Switch, a system dominated by first-party titles? Or is the outside-Japan audience for Monster Hunter mainly on PlayStation & Xbox? Will Switch owners in North America and Europe bite like PS4 & XBO owners did with World? Rise is going to be very popular in Japan, where it will almost certainly go on to become to be the best-selling third-party game ever on the Switch, and possibly even the best-selling third-party game ever in Japan (MH Freedom 3 on the PSP holds the current title with 4.5M copies sold at retail). But in North America and Europe, will it have widespread popularity like World did? There's just no way of knowing. It's going to be a huge hit. It's going to be the best-selling non-Nintendo game on the Switch, and definitely one of the best-selling third-party games ever on any Nintendo system. But will it sell well over 10M copies worldwide and dethrone Just Dance 3? That may not be an easy task. Not all records are made to be broken.