Invoicing should be optimized by allowing all elements of the invoice to be changed manually. I use GHL in English because the translation into German is miserable and as a result the invoices are also formulated in English. If you set the platform language to German, the elements are also displayed in German, except for the date format!
It should also be possible to customize the email that is sent when the invoice is created and save it as template. This looks much more like a scam..