One of the standard ways to counteract the loss of thrust when one engine quits on a twin is to put right thrust on the left engine. The loss of the RH engine will apply torque where you don't want it. The loss of the LH engine will not be a drastic shift in applied torque. The obvious answer to straight and level flight is to have both engines running with equal thrust. Obviously if they rotate in opposite directions all will be well as long as they are both operating. The loss of power on one side can be catastrophic depending on altitude and direction. In full scale aircraft the immediate application of rudder is required while feathering the offending prop. In that case you can feel the difference but RC has no stick feedback to help you. When Piper first came out with the Apache we had a problem checking out new multi-engine pilots. They often feathered the wrong engine and wore out the starter brushes trying for a restart. Many an airplane came back to the field on a truck. Finally with the aid of an accumulator we had an unfeathering kit. Wish we could put it on models. All that aside it is fairly easy to set up an electric by reversing one motor and you can run both on one set of batteries guaranteeing that both will quit at the same time. For nitro engines you will have to acquire one that can be reversed.