When you first join a friend's world, your skin will often change to their skin. If you try to change yours back, it will also affect theirs. This issue is with custom skins.
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[Mod] OcelotOnesie
migrated
Thank you for your report!
However, this issue is a Duplicate of MCPE-48207.
If you would like to add a vote and any extra information to the main ticket it would be appreciated.
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