The LTE frequencies are there, but the CDMA radios are not. Whether or not the phone is VoLTE capable on the Verizon Wireless network, I don't know. The LTE frequencies might not be enabled either. You also need to ensure it is SIM unlocked from AT&T before you try to move it to another carrier. iPhone 6 - Technical Specifications
I'm most definitely NOT a VZW employee. If a post answered your question, please mark it as the answer.