Nintendo includes sales numbers for their successful games in their financial reports so they are well represented but wikipedia also includes 3rd party figures when the publisher has released the numbers.
The top 5 3rd party titles*:
Monster Hunter Rise
Starview Valley
Sulka Game
Minecraft
Momotaro Dentetsu: Showa, Heisei, Reiwa Mo Teiban!
* I have overlooked titles like Pokemon and Hyrule Warriors as they are published by Nintendo in some regions.
There is an interesting list here;
https://en.wikipedia.org/wiki/List_of_best-selling_Nintendo_Switch_video_games
Nintendo includes sales numbers for their successful games in their financial reports so they are well represented but wikipedia also includes 3rd party figures when the publisher has released the numbers.
The top 5 3rd party titles*:
* I have overlooked titles like Pokemon and Hyrule Warriors as they are published by Nintendo in some regions.