You need a pam workflow or a Java class. Once a Catalog request has started a PAM process or a Java class, you can do whatever you want.
To interact with hyper-v I do believe you need SCVMM.
The easiest way would be to have template defined in vsphere and in SCVMM.
You can then display those template in a Service Catalog offering. Start a PAM workflow or a javaclass and call either vSphere or SCVMM.
vSphere has a rest API and SCVMM needs to be called via powershell with a cmdlet (Not sure how powershell cmdlet would be called from Java so I would suggets a PAM workflow).
Lots of fun ahead.