Overworld stuctures created with stucture block with outlines enabled are visible in the nether and end.
Create superflat world and create a stucture and leave it loaded with outline enabled
Go to another dimension.
Outline will be in a similar place as overworld one.
Thank you for your report!
We're actually already tracking this issue at MCPE-75231, so I will resolve and link this ticket as a duplicate.
If you would like to add a vote and any extra information to the main ticket it would be appreciated.
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