Possibility of importing virtual machines from other platforms
Currently proxmox does not have a module or component of how it could be integrated with other platforms for example: how to import virtual servers from openstack or xen
It is possible, there are many examples in the forum pages. I personally migrated vmdk (VMware) vdx(xenserver) and KVM hypervisors. I don't know if it is possible with Hyper-V but I would migrate Linux from any platform
While the answer is yes, unfortunately at the time of writing importing ova files for example isn't a gui based thing. An example is here: https://www.itsfullofstars.de/2019/07/import-ova-as-proxmox-vm/
For your specific user case however, I dont see a simple migration path.
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