Breath of the Wild 2 -- This is the only one I'm not sure we will be getting a sequel to. There is precedent for it, as shown by Ocarina of Time and Majora's Mask, not to mention, as I stated with Mario Odyssey, this would be relatively easy game to make as there is already an engine for it. If we do see this game, I say it comes in 2021.
NES, N64, Gamecube, and Wii all received 2 original (not remakes) Zelda releases. Actually, Gamecube and Wii shared Twilight Princess (the way that Wii U and Switch share Breath of the Wild), so take your pick which one to credit with 2 releases. But that still makes 3 out of 6 Nintendo consoles to see 2 original Zelda releases on the same hardware. Anyway, the fact that Breath of the Wild was available at Switch launch (having been developed originally for Wii U) pretty much guarantees we'll see another new Zelda game on Switch. I wouldn't expect it before 2022 though.
edit - 2021 is possible too