I just got a reply from @rmeyer at ALYF, the company behind the eu_einvoice app.
I was asking for the cost to adapt their application to make it work for Peppol UBL XML, but as he pointed out, the price would be a bit too much for one small company to bear.
So maybe this adaptation should be crowdfunded indeed…
Shout-out to Belgian users of ERPNext. I presume we are all in the same boat, as we need to be able to invoice and receive invoices in the XML format by 01/01/2026.
Who would be interested in a joint effort to tackle this?