Nintendo Switch Units Sold 139.36 million worldwide (as of December 31, 2023)

https://www.nintendo.co.jp/ir/en/finance/software/index.html

• Mario Kart 8 Deluxe - 60.58M
• Animal Crossing: New Horizons - 44.79M
• Super Smash Bros. Ultimate - 33.67M
• Breath of the Wild - 31.61M
• Super Mario Odyssey - 27.65M
• Pokemon Sword/Shield - 26.17M
• Pokemon Scarlet/Violet - 24.36M
• Super Mario Party - 20.34M
• Tears of the Kingdom - 20.28M
• New Super Mario Bros. U Deluxe - 17.20M