Mario x Rabbids is a million seller as well. wouldnt rule out Super Bomberman R as a million seller either. It should be really close if not already over 1M.
I'm referring to Vgchartz numbers only... and I don't counted M+R because of... Mario
Super Bomberman had a good boost last 2 months but I think will take more 7-10 months to reach a million (again, Switch version, VGChartz numbers).
If I remember well, SEGA announced Puyo Puyo above 1m months ago, too.