Changing the "Primary Geography" in the Account tab of Frase will automatically set the country you're searching Google in, and auto defaults to a language (though this can be switched) for each document created.
To alter these settings before creating a document, you can do so by clicking the "Country" and "Language" options.
For SERP research and optimization languages, Frase supports English, Spanish, French, German, Italian, Dutch, Portuguese, Danish, Norwegian, Finnish, Swedish, Romanian, Polish, and there are many countries are available for defining the SERP results.
If you just wish to use the in-editor AI writing (or AI Tools) in Frase, meaning no SERP research or optimization, more languages may be supported.