separate DNS Zone Contributor’s permission to create DNS zones and manage DNS Zone records
DNS Zone Contributor’s permission will allow the user to manage DNS zones and records, but will not be able to create new zone.
Please elaborate on the scenario. You can already provide permissions on a zone to a specific user such that user is able to manage records within that zone but not other zones. Please see https://docs.microsoft.com/en-us/azure/dns/dns-protect-zones-recordsets#zone-level-rbac