In order to get Unreal Engine to detect both of your controllers, you need to make sure that your controllers are properly configured and recognized by your operating system first. You can check this by going to the Windows Device Manager and making sure that both controllers are listed under the “Human Interface Devices” category.
Once you have confirmed that both controllers are recognized by your operating system, you can then move on to configuring them in Unreal Engine.
First, you need to go to the “Project Settings” and then navigate to the “Input” section. Here you should find a list of all the inputs that your project is currently using, including the ones for controllers.
Next, you need to check that the input mapping for each controller is set up correctly. You should see a list of inputs for each controller, such as “Left Stick X Axis” or “A Button”. Each input should have a corresponding input mapping, such as “Gamepad Left Stick X” or “Gamepad A”. If the input mapping is not set up correctly, you can click the button on the left of the drop-down menu and press the corresponding button on your controller to set it up.
You should also make sure that you have set up the correct number of players in the “Game Mode” settings of your project.
If you’ve followed these steps and you’re still having issues with only one controller being recognized, you may want to try restarting the editor, the game and your controllers.
Also, you can try to test the controllers on other games or software just to make sure the problem is not caused by a malfunctioning controller.