Linker::formatComment will currently format any wiki links as links to the local wiki. It should get an additional parameter, $wikiId, that would cause any links to be interpretet as interwiki links to that wiki. Linker::formatComment() It uses Linker::formatLinksInComment() internally, which already supports the $wikiId parameter for this purpose, so formatComment would just need to pass it through. formatAutocomments() may also get such a parameter, but since it returns wikitext which will then be processed by formatLinksInComment, care must be taken to not apply the interwiki prefix twice.

Rationale: Wikibase injects edit summaries from the data repo into clinet wiki's recentchanges tables. These comments should be formatted so that wiki links point to the data repo, not pages on the local wiki.