Can I Transfer a Digital Game or DLC to a Different Nintendo Account?
It's not possible to transfer digital purchases from one Nintendo Account to another. However, downloaded content isn’t limited to the Nintendo Account that made the purchase. When you load a Virtual Game Card on a console, anyone that uses that console has access to that digital game or DLC.
Please make sure that you are signed in to the correct Nintendo Account when purchasing or redeeming a game or DLC.