For a standalone wiki trying to do something similar (but without the potential of benefiting from and contributing to Wikipedia article discussions), see WikiClaim.
Topic on User talk:Tgr (WMF)/claims
Hi Gergo! Devin from Wikiclaim here :). This is a very well written essay! Do you have any ideas for how we could make Wikiclaim benefit from and contribute to Wikipedia article discussions? I'm all ears!
At a minimum that would require some kind of unique indexing of claims, much like how Wikidata is indexing things (as opposed to just deduplicating claims within a single article, which is already hard enough). But more generally it seems hard to do without embedding the claims functionality directly into Wikipedia somehow.