So what scheme should be taken to obtain the probability of the conditional measurement of m_0? Since it involves a measurement to get its probability value, I am very interested in knowing the probability of m_0 when it is the base state 0. Can snapshot read it please?

This functionality is not available in PennyLane just yet. Thank you for your input! Our team is working so that it’ll be available in the future. For now, all probabilities and states are calculated at the end of the circuit.