When a plugin creates its own .page file, it can have all the necessary translations for that page, including the title of that page.
You need to create a translation file with the appropriate name to get translations automatically included.
For example the URL for the File Integrity settings is http://tower/Settings/FileIntegrity
Then the file fileintegrity.txt holds the translations of that page.
A number of plugins do this already, you might want to look at these.
Of course plugins themselves must be written to support translations.
There is a guideline document, but can't find it at the moment.