With hedging MT5 can open a long and a short trade for the same robot at the same time. With netting MT5 can either open a long trade or a short trade with the same EA but not both at the same time. The EAs / robots do not determine if hedging is used. When you open an account with your broker and chose to use MT5 typically you have the option to select hedging. To change from hedging to netting you need to contact your broker and have your account changed to netting.
Alan,