Hello @Sumeet F ,
Welcome to Microsoft Q&A forums!
You can enable replication to Azure storage using PowerShell or Rest APIs but not through Azure portal. Please refer to the FAQ link - https://learn.microsoft.com/en-us/azure/site-recovery/vmware-azure-common-questions#can-i-change-the-managed-disk-type-after-a-machine-is-protected and the snippets below.
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