I want to know if I can detect my engine is having hesitation/stumble problem from an OBD. I mean not from any fault codes, but from the parameters obtained from the OBD. e.g. calculate the obtained torque/power and compare with the power/torque demand (from OBD PID) and say if the engine is having hesitation/stumble
A stumbling engine should result in abnormal engine vibrations. It should be possible to use the knock sensor(s)/misfire counter to detect abnormalities.
Note that it will not be as straightforward as setting a simple threshold-based limit since the normal sensor readout will be heavily dependent on factors like engine speed.