Setting default language and region for new documents


I’m running Nextcloud with OnlyOffice.

I have the following options set in /var/www/nextcloud/config/config.php:

  'default_locale' => 'en_AU',
  'force_locale' => 'en_AU',
  'default_language' => 'en',
  'force_language' => 'en',

But I notice that when I create a new .docx file inside Nextcloud and open it with OnlyOffice, the default language is English (United States).

Is there an option to set forced default language for newly created files?

Thank you.