Coming from Nintendo...
Several methods can be used to add friends as quickly and easily as possible: · By linking Nintendo Switch to your Nintendo Account, your friends from Miitomo and Super Mario Run will appear as friend candidates so you can easily send them a friend request. Also, we are planning it so that friends from social networking services will be listed as candidates, too.
In the future, you will be able to send a friend request to friends associated with your NNID (Wii U/Miiverse) and Nintendo 3DS.
In some games you will be able to use an in-game interface to send friend requests.
You can send friend requests to those who have played with you recently.
You can establish a friend through local wireless communication.
You can also send a friend request by using a friend code.