Super Bomberman R supports one or two players in story mode and four or eight players in battle mode (with COMs making up the numbers if required); there's nothing in the middle, so you need eight Joy - Cons, and there's no reason to have bought three
additional pairs yet.
In their study, they did not find a single exception, and they expect that the
additional 1,000 species that swim in this way (median /
paired fin swimmers) but that have not
yet been measured also will adhere to the OSW.