Instructions
Trade Friend Codes with another Pokemon trainer that has a Paras from a compatible game to trade via Wi-Fi. If trading via DS connection, you must be in the same room.
Fly to a town that has a Pokemon Center such as Jublife City and Eterna City.
Walk upstairs and talk to the woman behind the second desk to conduct a trade via Wi-Fi or DS connection. If you have not registered the other trainer's friendship code, do so in the basement of the Pokemon Center before conducting a Wi-Fi trade.
Follow the on-screen instructions to connect to your friend's DS and conduct the trade. You will need to trade one of your unwanted Pokemon for your friend's Paras to complete the trade.