Currently ContentTranslation adds "contenttranslation", "contenttranslation-v2" change_tags to Wikipedia edits. However, when articles are linked in Wikidata there is no change_tag.
Adding change_tag also to Wikidata edits would allow querying the language links additions afterwards on ToolForge which is currently impossible as one would need to query them from revision_comment using text-search which is super slow.