Magellan allows you to combine different publications into one online help output. For example, publications for different variants and different languages of your book.
You still have to publish the variations individually, but can combine them in one searchable site. Different locales will become available in the menu bar. You can configure the Filter tab in the output based on these different publications.
To setup a site with multiple locales and variants, update the themeconfig.json file (your customized version of the siteconfig.json file).