Before trying to answer your question, I would like to clarify a few aspects about Availability Zones.
(1) Availability Zones physically and logically separated datacenters with their own independent power source, network, and cooling. But they are in the same region. So they provide resiliency only to datacenter failure, but not to regional failure. More details: [https://learn.microsoft.com/en-us/azure/reliability/availability-zones-overview
(2) A single AKS cluster can be created in one region. For an AKS cluster, availability zones can be defined. More details: [https://learn.microsoft.com/en-us/azure/aks/availability-zones
However, I understand you would like to have a second AKS cluster that would allow you to use Traffic Manager to distribute the traffic between the two AKS clusters, in case one goes down. So, if you are looking to protect from regional outage, from (1) and (2) we can conclude a new AKS cluster (in a different region than the current one) is required for your setup. Also, if you want to have availability in case one cluster is down (but you don't care about regional outage scenario), you need to create a new AKS cluster, in the same region or another region.
Now, to attempt answering your question, I would say you need to deploy a new AKS cluster and deploy your application there. To help you with this task, you can make use of Velero (note this is open-source tool, not Microsoft) and AKS node pool snapshot. Please make sure to read the documentations before starting to use them to understand the use cases and limitation (for example for node pool snapshot, you can only use the snapshot in the same region as the source node pool).
For the Azure Traffic Manager scenario, I am sure you will find this documentation helpful: [https://learn.microsoft.com/en-us/azure/aks/operator-best-practices-multi-region#use-azure-traffic-manager-to-route-traffic
I hope this answers your question.
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