Yes, LG Q6 Plus does have the VoLTE.
Yes, LG Q6 Plus does have the Corning Gorilla Glass.
No. LG Q6 Plus does have the LED notification light and it also has the Always-On display.
Yes, LG Q6 Plus does have the face recognition. You do not even require to power up your phone. It's camera automatically detects your face and unlocks the phone more quickly than typing, drawing or fingerprinting.