Hello Michael
Welcome to Microsoft Q&A Platform, thanks for posting your query here.
I reached out to internal team to check on this ask. Yes, currently there isn't any external support for ARM64 running on Batch.
To see a list of the virtual machine sizes that are currently available in Azure Batch in a specific region, you can use the following Azure CLI command:
az batch location list-skus --location <location>
Replace <location>
with the name of the region that you are interested in, for example, "eastus". This command will return a list of virtual machine sizes that are available in that region for use with Azure Batch.
Ref: https://video2.skills-academy.com/en-us/cli/azure/batch/location?view=azure-cli-latest#az-batch-location-list-skus
Hope this helps.
If you need further help on this, tag me in a comment.
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