vDS is NOT a pre-requisite for NSX Guest Introspection
This seems to be a common misconception both from customers and third party vendors, the vDS is also not licensed as part of NSX in the “NSX for Endpoint” license. Therefore a normal VSS standard vSwitch is fully supported for deploying NSX Guest Introspection to use with third party vendors i.e. for Anti Virus.
Please refer to the NSX 6.x Installation Guide on how to use the “Specified on host” option when deploying Guest Introspection
Extract from the NSX 6.x Installation Guide Below…