Nintendo won’t let you use a microSD card on multiple Switch systems.
Trying to transfer a microSD card from one Nintendo Switch to another will bring up a warning, according to Polygon. The message says:
“The microSD card is being used by another Nintendo Switch console or was used on this console before it was initialized. Delete the Nintendo Switch data on the microSD card to use it on this console.
Save data, screenshots, and other data not related to Nintendo Switch won’t be deleted. You can remove the microSD card if you don’t want to use it on this console.”
Author: Evan Campbell