This is a tool to make it easier to find external links on several wikis. Combines Special:LinkSearch and Special:SiteMatrix. This will be a powerful tool for use with communication with external organizations like GLAMs to persuade them to cooperate with the Wikimedia movement.
The search page can look exactly like the existing page.
The query should then be put to all the wikis.
Results should be in several sortable tables. And at the top there should be a summary with how many links there are, how many unique links, how many unique articles they are used in. It would be nice if these key figures could be queried through an API.
The first table should be a summary per project with the headers; project, language, # links, # unique links, # articles using them. Each row should be a link to that local link search. Default sorted by # links descending. Filtering on language and/or project would be nice to have.
The second table should be a summary per link with the headers; link, total times used, # language projects, # languages, # projects. Default sorted by total times used descending. Each row should be a link to a detail table.
The detail table should list all uses of one link with the headers; project, language, namespace, article.