Rather than starting from scratch, would it make more sense to make an ActivityPub plugin for the open-source MediaWiki software Wikipedia runs on? MediaWiki already has some “interwiki” functionality that such a plugin could expand on, and you’d have the advantage of being able to fork content from WP and other MW projects without having to re-format it. Plus you’d be able to leverage other MW plugins—Semantic MediaWiki in particular could add a lot of useful functionality to federated wikis, like articles that could query and aggregate information from other federated articles rather than just linking to the text.