Hi Pieter,
AFAIK, this is not supportted at this moment.
Azure DNS doesn't currently support zone transfers. DNS zones can be imported into Azure DNS by using the Azure CLI. DNS records are managed via the Azure DNS management portal, REST API, SDK, PowerShell cmdlets, or the CLI tool.
The zone transfer feature is tracked in the Azure DNS backlog. Use the feedback site to register your support for this feature.
Hope this helps.
JS
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