I've got the same issue.
Airpods works perfectly on all devices (Apple and other) and also work on my laptop (both speakers and microphone).
When using MS Teams only the microphone works and not the speakers. The issues lies therefore within Teams itself
I've looked at the MS Teams settings which recognizes the Airpods.
There are many comments/questions on communities for a number of years stating exactly the same for both Skype and Teams but no solution from Microsoft so far.
Please advise how to make my bluetooth earpods work.
I have been using AirPods with Teams for roughly the last year and have had this same issue from time to time, mostly due to my other Bluetooth devices "stealing" the AirPods.
However, for the last week or so I have had it constantly. AirPods will connect to the laptop but when I start a Teams call, I can be heard but can't hear others. Once or twice I have been able to open and use my AirPods after the Teams call is in progress, but not when starting up a call. Then when I switch to another call, even if they are back-to-back, suddenly the AirPods won't receive audio again.
Bottom line, lately the issue has been that the AirPods won't connect to receive audio when entering a call.