Hello alium,
after your helpful tip, I searched again in the AUR and found an actual package for this driver.
HP_ProDesk:[roberto]:~$ trizen -Ss epson-inkjet-printer-escpr
aur/epson-inkjet-printer-escpr 1.7.9-1 [installed] [40+] [1.50%] [15 Mar 2021]
Epson Inkjet Printer Driver (ESC/P-R) for Linux
So I uninstalled the old driver and installed the actual driver.
After setting up my printer via localhost, I get the same error message
The printer "EPSONBF506F.local" cannot be localized.
I have tried both the driverless version
ipp://EPSON%20XP-312%20313%20315%20Series._ipp._tcp.local/
and the regular version via dnssd.
dnssd://EPSON%20XP-312%20313%20315%20Series._ipp._tcp.local/?uuid=cfe92100-67c4-11d4-a45f-b0e892bf506f
The only way to persuade the printer to print is still via lpd.
Many greetings
Roberto