【Updated: 】
Below are the Mii characters that can be used in the app.
・ Mii characters that were made with the Nintendo Account that is linked to the app.
・ Mii characters that were added using a Mario Kart Tour Mii Number.
Note: Please see "What are Mii numbers?" for an explanation about Mii numbers.
You cannot use the Mii characters of a Nintendo Account that is not linked to Mario Kart Tour.