In general, in a configuration where phases of the encoder from the Master inverter are connected to input terminals of the A8AL card in the Slave inverter, during synchronization ( Pr.419="1") Slave inverter follows the rotation direction of the Master inverter and it's position. There's no possibility of switching the direction of the Slave inverter (Master run forward and Slave run in reverse) other than electrically switching the A and B phases together.