Some exchanges have exchange coin that can be used to reduce the fees of order's execution.
This amount won't be allocated to your portfolio if you don't have this coin in your portfolio. In cas you have some exchange coin, a reserve amount can be choosed to it from being sold. You can enable this functionality in Crocobot with a positive amount:
Binance
BNB is the Binance Coin to reduce 25% of your fees.Enable BNB Deduction on orders fees on Binance: