Hello Martin,
Welcome to Microsoft Community.
We have queried Teams for this feature, please allow me to share our results with you here.
- The green screen feature in Teams is available in a public preview in April 2023, which you can find in the link below:
Now in public preview: Green screen feature in Teams Meetings | Microsoft Community Hub
And there's a key message:
It is only supported on Windows and macOS devices using Intel and AMD chips.
- After we logged into Teams on Surface Pro 10(with Intel CPU) using a personal account, we did not see the "Green Screen" option in the Devices Settings, suggesting that this feature may not be available to individual users:
Using Green Screen in Microsoft Teams - Microsoft Support [290a-bb62-24c-dea3]
Note that in the list to the left of the screenshot, some options are only shown in the organization version.
If it's convenient for you, could you clarify for us whether you are logging into Teams using an individual account or an organization account on an Intel-based Surface device?
You can click on your account avatar to send us a screenshot.
Best Regards,
Mitchell | Microsoft Community Support Specialist