In the Wikimedia Incubator, there are test wikis for multiple projects and languages all collected in one wiki. Due to intentional design limitations in Wikidata, only one page from each wiki can be connected to an item. However, in the Wikimedia Incubator, there can be dozens of pages that would belong to the same Wikidata item, but in different languages (and/or projects). In order for pages like this to be able to benefit from Wikidata to fetch interlanguage links and data to populate infoboxes, we could have a parser function that tells the software that this page should fetch relevant data from item X.
The current situation is that the relationship only goes one way, that is Wikidata -> client wiki. This parser function would let it go the opposite way.
This would be useful for:
- Wikimedia Incubator
- Multilingual Wikisource
- Beta Wikiversity
- Possibly also other multilingual wikis that have pages in more than one language on the same topic
I'll add a suggestion for implementation in the comments.