Using separate BluetoothHFP devices for input and output

I want to connect a BluetoothHFP microphone to MFi hearing aids. Whenever I make the microphone the input it steals the output and whenever I make the MFi the output it steals the input. Is it possible to do this using AVAudioSession? Is it possible to redefine the MFi hearing aids as a speaker and use Live Listen?

Using separate BluetoothHFP devices for input and output
 
 
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