You are right and I already have done that, thank you, all supported services are active on the operator side and SIM is already provisioned; now Asus has to certify that their device can make emergency calls over VoLTE and send the modem binary configuration file in a future update. But probably Asus is not wiling to jump through the certification hoops as they did for bigger networks like Vodafone or Orange...
I'm glad it works!
I find it interesting about the emergency call through VoLTE, I have not I find it about the emergency call through VoLTE, I have not tried it in my case. In your capture the video calls are deactivated, it is strange, because to me if they were activated. I show you in an old screenshot:
It seems reasonable what you say about the certification, but I think it is on the part of the operators who certify the devices.
Just two days ago I discovered that after restarting my phone, VoWiFi appeared automatically, without entering the code. And in the VoWifi options appears a new option to use it through roaming. This is why I think that O2 / Movistar Spain is the one who has certified ZF9 to use VoWifi.