Internationalization of customer surfaces

Hi,
our storefront supports both English and German. Is there currently a way to set the language or locale of the embedded storefront and checkout, for example through Moonbase.setup()?

Ideally, when our website is set to German, the complete checkout UI should also appear in German. I could not find a documented locale or language option.

Is this already supported, or is localization planned?

Cheers,
Marc