Twig Translation String without Enabling Interface Translation Is it possible to provide translation strings to Twig, without the Interface Translation module enabled? 

We have Content Translation enabled but do not want to enable Interface translation (we would like the Drupal administration menu system to remain in English).

We have a couple of landing pages that base most of their content on a translated entity however, there are still a few labels and links we would like to translate using {{ 'foo'|t }} in Twig.

Is this possible? And if so - where would the translation stings be stored?
Our solution in the end was to create a new Twig extension called tr.

The class of the extension plugin checks to see if a 'translations' directory exists in the current theme. If it does, it reads the containing YAML translation files into an associative array (en.yml, es.yml, fr.yml etc.)

When {{ tr('source string') }} is called in the twig template, it will check the loaded associative arrays to see if there is a translation available for the current language and requested string. If there is it will return the translated value.

This works for us since in our case we're only translating a fairly short list of values - short strings and labels like 'Read More', 'Learn More', 'Subscribe' etc. The rest of our translated content comes from the content translation of the entities.

Hope this helps...