Port groups don't need vmk interfaces if they are for VMs.
Are you able to post a screenshot?
There are Virtual Machine Portgroups and VMkernel Portgroups out there. Only the 2nd. one needs an IP address and all of those VMK are "for" ESXI rather than VMs.
Also there is no difference between vDS and vSS when speaking of VMKs.
Basically the VDS same as the VSS is made of portgroups where you can place just Virtual Machine or you can place VMkernels which provide you some functionalities such as vMotion, Management, Fault Tolerance, vSAN, etc.
For configuring a VDS you have to do the next:
- Create the VDS
- Assign the vmnics to the uplinks.
- Create all the porgroups with their respective VLAN tagged (In case you are using VLAN Tagging)
- Modify the Teaming and Failover policy in case needed (For example vMotion uses one Uplink as active)
After that you can use the VDS and you can choose to place Virtual Machines on those portgroups or simply configure VMkernel Adapters for the services mentioned above and for that it will require IP, Netmask and Gateway (Optional) as these last ones are just adapters like vNICs in a Virtual Machine.