Linguix Turbo user interface is in English and this language is the main one we work for. This means that some Pro features like grammar checking and rephrasing are available in English only.
However, you can create shortcuts with the content in any language:
The only thing for you to keep in mind is that Shortcut name and Title should be written used Latin characters, preferable in English. The content of the shortcut itself is completely language-independent, so you can use any language you want!