This feature, available only in Polylang Pro, allows you to translate the URL slugs for post formats, custom post types, custom taxonomies, as well as category, tag, author, page, attachment… The example below is for the slug ‘category’ but translating other URL slugs works the same way.
Let’s say that you have created a category in French and its English translation. By default your categories URLs would look like:
As you can see, the slug ‘category’ is identical whatever the language.
Go in Languages > Strings translations
Notes: You can filter the strings translation by the group ‘URL slugs’. If some languages are missing, make sure that the admin languages filter displays “Show all languages”.
In the example below the string ‘category’ is translatable in French and in English. Translate the URL slugs in the Translations column, then click on “Save changes”.
Once done, your categories URLs look like: