Current Setup:

• 2 x Nintendo Switches (both with their own physical copy of Minecraft and are installed/updated to the latest available version
• Family Nintendo Account (baldie1843, my wife, my 9yo son, and my 4 yo daughter).
• Realms Plus setup under baldie1843

Problem:

• If one person logins into the Realm on Switch A, no one in the family account (with subscription) can log in from Switch B.

How to reproduce:

• Setup Family plan with at least 2 family members.  One of them should be a child/restricted account
• Log primary (in case me baldie1843) into the Realm from Switch A
• Attempt to login child/restricted account into the Realm from Switch B

In theory any Bedrock client should cause this issue, and not just the Nintendo Switch, as it indicates that the secondary user (in this case child/restricted account) is already logged into the Realm on a different device.

Observations:

• It looks like it is referencing all accounts in the family account as the original/parent account (in my case baldie1843).
• When logging multiple users in to the same switch (split screen), it shows the first user as the primary family member (baldie1843), and the others use their Nick names defined in the local switch (mommy, bubby, peaches, etc).
  • (This might be an indication of a second issue, or just another symptom of the same issue.)