I have built an arena.
For PVP, I used lots of barriers to stop TNT explosions from exploding outside the battle area.
Any person at one side of the arena sees glitches on the other side.
Video
https://drive.google.com/file/d/1hE9-zgfZNDKvDlQLkuqLBQX2Tb72LhJZ/view?usp=sharing
They may still be processing the video.
Thank you for your report!
We're tracking this issue in MCPE-153515, so this ticket is being resolved and linked as a duplicate.
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