Retail exclusives:
ARMS
Bayonetta 2 (1 is also available on Switch)
Captain Toad: Treasure Tracker
Donkey Kong Country: Tropical Freeze
Hyrule Warriors: Definitive Edition
Kirby Star Allies
Gal Metal
Mario Kart 8 Deluxe
Mario Tennis Aces
Mario & Rabbids: Kingdom Battle
Monster Hunter Generations Ultimate
New Super Mario Bros U Deluxe (releases January)
Octopath Traveler
Pokken Tournament
SNK 40th Anniversary Collection
Splatoon 2
Super Mario Odyssey
Super Mario Party
Super Smash Bros Ultimate
Sushi Striker: The Way of Sushido
Taiko No Tatsujin: Drum N' Fun
The Legend of Zelda: Breath of the Wild
The World Ends With You: Final Remix
Xenoblade Chronicles 2
Switch exclusive Indie games:
Blaster Master Zero
Blossom Tales: The Sleeping King (Available on PC, but console exclusive on Switch)
Bomb Chicken
Debris Infinity (Available on PC, but console exclusive on Switch)
Fast RMX
Flat Heroes (Available on PC, but console exclusive on Switch)
Into the Breach (Available on PC, but console exclusive on Switch)
Mighty Gunvolt Burst
Golf Story
Kamiko
Mini Metro (Available on PC, but console exclusive on Switch)
Pocket Rumble (Available on PC, but console exclusive on Switch)
Pode
Severed (Available on mobile/PS Vita/Wii U, but not on other consoles)
Snipperclips
SpiritSphere DX
Wandersong (Available on PC, but currently console exclusive on Switch)
Retro recommendations:
Arcade Archives: Donkey Kong
Arcade Archives: Excitebike
Arcade Archive: Punch-Out
Arcade Archives: Sky Skipper - (This is the first time that this game has released on consoles)
Arcade Archives: Super Mario Bros
Gunbird 1 + 2
Johnny Turbo's Arcade Night Slashers - (This is the first time that this game has released on consoles)
Ikaruga
Sega Ages - Lightening Force: Quest for the Darkstar
Strikers 1945
Non-exclusive recommendations:
These aren't exclusives, but they are fun games to play in portable mode:
ACA Neo Geo: Garou: Mark of the Wolves
ACA Neo Geo Magical Drop 3
ACA Neo Geo Metal Slug 1 and 3
ACA Neo Geo: Neo Turf Masters
ACA Neo Geo: Waku Waku 7
Battle Chef Brigade
Bleed 2
Capcom Beat em up Bundle
Celeste
Child of Light
City Skylines
Civilization 6
Cosmic Star Heroine
Dead Cells
Diablo 3
Enter the Gungeon
Flinthook
Graceful Explosion Machine
Hand of Fate 2
Hollow Knight
Horizon: Chase Turbo
Iconoclasts
Just Shapes & Beats
Katamari Damacy: Reroll
Lego City Undercover
Lovers in a Dangerous Spacetime
Lumines Remastered
Minecraft: Switch Edition
Night in the Woods
Overcooked 1 + 2
Pac Man Championship Edition 2
Puyo Puyo Tetris
Rocket League
Runbow
Salt & Sanctuary
Shantae and the Pirate's Curse
Sonic Mania
Stardew Valley
Steamworld Dig 2
Steamworld Heist
The Messenger
Thimbleweed Park
The Banner Saga 1, 2, 3
Toki Tori 1 + 2
Transistor
Undertale
Valkyria Chronicles 1
Valkyria Chronicles 4
Wild Guns Reloaded
Wonder Boy: The Dragon's Trap
Worms W.M.D
Yoku's Island Express