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.
Yes, LG G6 Plus does support VR. It has the Gyroscope sensor.
No. You cannot change the color of the notification light in LG Q6 Plus.
No. LG Q6 Plus is not a water-resistant phone but it is made of incredibly strong 7000 series aluminium.