Strattic supports WPML, a WordPress plugin that lets you add languages to your WordPress sites easily.
Using WMPL with Strattic
We currently support directories, but not subdomains or parameters.
You will need to update this setting in order to ensure WPML works with your static site.
Go to WPML > Languages and make sure the Language URL format is set to “Different languages in directories”.
When that is done, add languages and content as you normally would, when you are ready to publish, run a full publish to the static version of your WordPress site.