Is VoLTE possible on this board?

Is VoLTE possible on the Base HAT?

If not is there another board I could use instead? It would have to be 4G/LTE, 3G and VoLTE compatible.

Thanks in advance.

Yes, the VoLTE is supported by the EC25 module used with the Baes HAT.

Make sure it can be done with the SIM card you are using.