Vous avez essayé cette méthode ?
How to Transfer Nintendo Switch Data to an SD Card
You can transfer games and other software you've purchased through the Nintendo eShop to a microSD card for use on another Switch console:
With your Nintendo Switch turned off, insert the microSD card into the back of the system.
Power on your Switch and select System Settings on the home screen.
Scroll down and select Data Management > Manage Software.
Select the games you wish to transfer.
Select Archive Software.
Select Archive.
Select OK, then press the Home button on your Switch controller to return to the home screen.
Select the game from the home screen, then select Download to save the game data to the SD card.
When a microSD card is inserted in the Nintendo Switch, it becomes the default destination for downloaded software.
You can now insert the SD card into a non-primary console to play the game without an internet connection.
Je ne comprends pas l'anglais :/