Hi,
I kind of wrongly understood the original question, so I wrote a more general SPARQL query¹ to get this for languages in Wikidata.
Might be of some interest for someone, so I'm posting it anyway:
--- 8< ---
SELECT ?name ?localname ?iso3 WHERE { ?language wdt:P218 ?iso1 ; wdt:P220 ?iso3 ; rdfs:label ?name . FILTER(LANG(?name) IN ("en")) . OPTIONAL { ?language rdfs:label ?localname . FILTER(LANG(?localname) IN (?iso1)) .} } ORDER BY ASC(?iso3)
--- 8< ---
Best regards,