In order to better address translator coverage for major, non-English sources (T94170), it would help to have lists of the most needed translators for each (major) language Wikipedia. See T96927: Evaluate citoid for citations used on Wikimedia sites for two-year-old dumps of each language Wikipedia's most referenced domains, sorted descending. (Also re: the Swedish list, see P691 and discussion in T94170#2534552.)

A research write-up was published on Meta and resulted in two comparisons of the most cited domains in need of translators on enwp and on frwp. We could use the same treatment for the other languages.

We either need the most cited lists re-dumped (see research pub on Meta for the methods) or that list analyzed against Zotero translators. (Either feed each site into the Citoid citation autocomplete tool, or use Zotero browser plugins to determine which translator is triggered for the site and whether Embedded Metadata sufficiently cover the site.) Tables like the enwp and frwp linked above wouldn't hurt.