Categories don't work in translatewiki.
https://translatewiki.net/wiki/MediaWiki:Welcomecreation/aeb
https://translatewiki.net/wiki/Category:Delete_Requests
Categories don't work in translatewiki.
https://translatewiki.net/wiki/MediaWiki:Welcomecreation/aeb
https://translatewiki.net/wiki/Category:Delete_Requests
Please describe what "don't work" means.
Also see https://www.mediawiki.org/wiki/How_to_report_a_bug
I'm not aware of categorylinks being needed in namespace MediaWiki. For sure, we don't need them on translatewiki.net and it was an issue when they were registered in the past; closing.
Besides, we don't use that category. https://translatewiki.net/w/i.php?title=Special%3AContributions&contribs=user&target=Mjbmrbot&newOnly=1 did the job (all deleted now) and Special:Nuke would have too, had you not touched the pages further.