With the 2023.1 (Antelope) release Designate received the ability to share zones.
Would be awesome to have this capability accessible via Gophercloud.

There also is an issue for the OpenStack Terraform Provider to implement this - terraform-provider-openstack/terraform-provider-openstack#1692

Further links about this feature ....

• https://docs.openstack.org/api-ref/dns/dns-api-v2-index.html#shared-zones
• openstack/designate@f39704d
• https://bugs.launchpad.net/designate/+bug/1714088