Hi
Since you didn't mention much detail about your WVD subscription architecture.
- It is always recommended to deploy WVD machines in a separate subscription. It become more easy to manage and avoid conflict policy with VM in azure and also cost management.
- If all your machines are windows & you planning to adopt MDE agent on all machine in the subscription , you can enable simply in Defender for cloud - Environment Setting - Expand & select your subscription - Defender Plan - Servers : Configure - Enable the endpoint.
- This setting will start pushing MDE agent in all machine.
- Refer snapshots
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