Agree, there doesn't seem to be a supported solution for this migration path. You can do VMWare to ASR, but it may not work the other direction.
Setup Azure Site Recovery for Azure VMware Solution VMs
This thread suggests the only other way is to download the OS VHD and then convert it to VMDK for upload into the datastore. Seems a lot of downtime would be needed.
Migrating VM from Azure to VMWare
Please upvote and accept this thread as answered if it's helpful, thanks!