When you have translated your content you'll use the publishing options in the Library or Author. The publishing process automatically uses your localized variant object templates to control the settings (and text strings) required for your output and the translated variable values stored against the Locale record.
- Publish the variant book to use the translatable properties on the localized book object (to use the translated book title and other fields).
- Publish the primary book to use the properties for the source language.