Translation and language relations
Check the assignment of both translations in the language plugin. Two independently created contributions do not become a language pair solely through similar slugs.
With WordPress, language URLs are often linked by an extension. Check whether the affected contributions belong together as translations and whether both have been published. Even inserted hreflang tags may differ from this assignment.
Where to check the setting in WordPress
In the translation tool used, open the assignment of the affected contribution. Compare published translations with the hreflang URLs in the head; a manually inserted language link in the menu does not automatically generate this assignment.
Example of this specific finding
Illustrative control case: The German side calls the English version, which knows only itself. The language set is incomplete.
follow-up audit in WordPress
Test each published translation with their canonical and counter references. The mere existence of a language flag does not confirm a correct language set.
Retrieve the assignment from both URLs and supplement backlinks. For multiple languages, check the entire set instead of just a single pair.
Derogations and scope
A link in the voice menu does not replace the hreflang assignment. Both can come from different data sources.
Related: WordPress with classic or block theme. SEO plugins and page builders are different; there is no universal menu path for all installations.
Classify the general error
Definition, system-independent causes and further correction examples: Check language references as a related group