Streteched k8s cluster spanned on multiple Openstack clusters


I’m facing a question where I don’t have a clear answer and I thought I might find some help by people here.

Thanks to Juju/MaaS, we are now able to deploy Openstack clusters quite easily (still a few annoying bits here and there though) on bare metal and then, deploy kubernetes clusters inside Openstack tenants.
This is great and a good step in the direction we want to take.
However, I now have a recurring request from our users : can we deploy one k8s cluster spanned on 3 openstack tenants ?
The idea here is to have one etcd node + multiple workers per tenant.
I thought this might be possible by bootstrapping 3 openstack “clouds” in Juju then create a tenant in each cluster where you could deploy a k8s parts of this stretched k8s cluster.
Then, maybe you can “link” them together using Cross Model Relation ?

Well, this is what I suspect but this I’m still quite confused about this setup so any help or idea would be very helpful.

Best regards.