No. LG Q6 Plus is not a water-resistant phone but it is made of incredibly strong 7000 series aluminium.
Yes, LG G6 Plus does support VR. It has the Gyroscope sensor.
Yes, LG Q6 Plus does have the Google Assistant.
LG Q6 Plus SAR value is as follows:
SAR Value (Head): 0.72 Wkg@1g
SAR Value (Body): 0.455 Wkg@1g