Overview of the Issue
When you turn on Remove Category Base Prefix in All in One SEOSearch AppearanceTaxonomies, the category pages in your default language work, but the translated category pages show a 404 error.
Workaround
Keep the category base in your category links:
- Go to All in One SEOSearch AppearanceTaxonomies.
- Open the Advanced settings of Categories and turn off Remove Category Base Prefix.
- Go to SettingsPermalinks and click Save Changes.