Thread:Project:Support desk/Special watchlist - Not recently updated pages/reply (3)

Have you seen Special:AncientPages - it sounds sort of like what you are looking for minus the category part. Also consider extension:DynamicPageList (Wikimedia) which can generate lists of articles in some category organized by date.

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The type of thing you're describing can be written by anyone as an Extension. You will need to know PHP to do so. There are also several people who offer consulting services to write extensions for people.