I had never heard of Cloudbase-init for Windows until reading this post. I was inspired and found away to get it working with XCP-ng. Hope it helps someone.
Packer/XCP-ng Template for Windows that loads Cloudbase-init
https://github.com/mtcoffee/xcp-ng-packer-examples
Terraform/XCP-ng Template for Windows that leverages Cloudbase-init template
https://github.com/mtcoffee/xcp-ng-terraform-examples