https://news.xbox.com/en-us/2021/01/15/2021-xbox-exclusive-games/
There are 27 announced games that I counted from that article that are launching as console exclusives on Xbox Series X|S and Xbox One. I excluded Psychonauts 2, She Dreams Elsewhere, The Yakuza Remastered Collection, and Yakuza 6: The Song of Life since they will also appear or have appeared on other consoles but were listed above as Gamepass releases for the first time on Xbox.
Adios
The Artful Escape
The Ascent
The Big Con
CrossfireX
Dead Static Drive
Echo Generation
Exo Mecha
Exo One
The Gunk
Halo Infinite
The Last Stop
Lake
Little Witch in the Woods
The Medium
Microsoft Flight Simulator
RPG Time
Sable
Scorn
Shredders
Song of Iron
Tunic
Twelve Minutes
Unexplored 2 The Wayfarer's Legacy
Warhammer 40K: Darktide
Way to the Woods
The Wild at Heart
Toshiba 4K HDR 43" | i7 4770 | 16GB DDR3 Crucial Sport | Zotac GTX 1080 Mini 8GB | Noctua NF-A9 Cooling | 500 watt 80+ Gold PSU
Xbox One X | Xbox 360 S