The latest firmware update for the Nintendo Switch (version 10.0.0) brings a bevy of new features, including the ability to completely remap the Joy-Con and Pro controllers and the ability to transfer data (including games) from the Switch's internal storage to an SD card.
https://www.notebookcheck.net/Nintendo-Switch-System-Update-10-0-0-adds-controller-remapping-improved-file-management-and-more.461578.0.html