Hello @Badger ,
Welcome to Microsoft QnA.
Apologies for the delay in response, as I was internally checking on this query with the Stack HCI Team.
Yes, we do have this functionality in preview to currently deploy VMs on Azure Stack HCI cluster through ARM templates. The functionality is called Arc VMs on HCI and documentation for the same is available on the below link. Thanks.
Azure-arc-enabled-virtual-machines
Hope this helps. Do let us know if you have any queries, Thanks.
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