In Microsoft VDI environment, mostly people will use KMS for activate the client OS due to the Master OS is sysprep and the client OS will roll back after user logoff.
Once the Master copy is sysprep, the OS is shutdown and no matter the OS is activate with the license or not, sysprep will still make it unlicense.
This is how it will works.
System Admin will use the Master copy after sysprep (make sure to shutdown after perform the sysprep) to create client copy with no license activation in it. After that, system admin will use KMS activation so that whoever log in, it will search for KMS host and activate it