In the case of multilingual wiki (Wikidata, Commons, OSM wiki), there could exist pages in multiple languages all representing the same topic. Currently, it is only possible to store only one sitelink per wiki. One hacky workaround could be to store data as monolingual strings.
What would be the best way to change Wikibase to support multilingual wikis via sitelinks? Current sitelink system relies on wiki ID, not on language ID.