@Sachin.Panchal Thank you for your post and I apologize for the delayed response!
We need three appliances one for each environment. If we have more than one VMware environment, then we need that many appliances. This logic applies - https://learn.microsoft.com/en-us/azure/migrate/common-questions-appliance#can-the-azure-migrate-appliance-connect-to-multiple-vcenter-servers for all the sources (VMware, Hyper-V and Physical). That being said, we do not have unified appliance available as of now.
If you think this is one of the key requirement/enhancement that Azure migrate appliance should have then I recommend you to share this as a feedback directly to Azure migrate feature PM through UserVoice forum.
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