Hello!

I'm tasked with fixing a problem with our company's custom made electric invoicing module for Odoo 13.0 that uses Finvoice 3.0 standard (https://www.finanssiala.fi/en/topics/finvoice-standard/) to send the invoices. The problem is that Finvoice uses ISO-8859-15 character encoding while Odoo uses Utf-8.
This causes our invoices to have weird characters when we have to send special letters of the Finnish alphabet which is a big problem as our customers are mainly Finnish companies and organisations.
Any ways to send data with the ISO character encoding from Odoo?