Hi Chris!
It sounds like your AirPods Pro work with your iPhone, but the microphone doesn't work when paired with your MacBook Pro. We've got your back!
With AirPods, the firmware is updated along with the paired iOS device. If your iPhone has an update available, we'd get that installed to make sure the firmware on your AirPods are also updated: Update your iPhone, iPad, or iPod touch Connect the AirPods Pro with your iPhone after updating to allow it to push any firmware updates, then pair them with your Mac to test.
Note: It's important to backup anything important prior to updating your device.
Turning off Bluetooth on your iPhone is smart, since it may cause some wireless interference when the AirPods Pro are trying to use the MacBook Pro's Bluetooth. To check for any other interference, check out: Resolve Wi-Fi and Bluetooth issues caused by wireless interference
Make sure the AirPods are set up properly for your Mac: Set up AirPods with your Mac and other Bluetooth devices
Should it persists, we'd try to Reset your AirPods
Let us know if that solves it, take care!