This is something I've occasionally thought as well. I've been thinking about making a thread about which Switch exclusives will get sequels ... because a lot of franchises that were once per console, yet twice per generation now suddenly have a big ? mark as to whether they'll get a Switch sequel.
I think Splatoon 3 and Mario Kart 9 could very definitely be Switch games.
Everything that released early has a good chance for a sequel, except for Super Smash Bros. Ultimate. Another 3D Zelda, 3D Mario, Mario Kart, Mario Party, Splatoon... three of those are very much expected to get sequels anyway. Pokémon will have several games if we combine regular and Let's Go variation, because Pokémon releases almost every year.