@Rising Flight, Thanks for posting in Q&A.
We can create a Conditional Access policy to block some users accessing Microsoft Teams on mobile phone but allow laptops/AVDs.
Here are some steps you can refer.
1.Go to Intune portal > Click Devices > Click Conditional access > Click create new policy.
2.Select Select users and groups under Users > Select Microsoft Teams Service under Target resources > In Conditions, select Android and iOS under Device platforms > Select Block access under Grant.
3.Assign the policy to user group.
Hope it will help.
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