Have successfully migrated 2 VMs from ESXI, doing MANY Hyper-v migrations, and have a suggestion / feature..
THIS is likely not the forum for this, but I know you guys are in a similar situation...

Is it possible to add within XOA or the XCP-ng Center to allow attaching to a hyper-v cluster and do drag and drop style of migrations from hyper-v to XCP?
I had something similar setup for a past company that allowed me to attach to any type of cluster and manage all from within a single pane of glass ( Until all migrations were complete )