How to add a new device input in ue4，not keyboard 、mouse、steamVR…
I’d guess that would likely depend on the device being added. For example, several joysticks out there for purposes like flight simulators, share a relatively universal control scheme which emulates that of I believe certain handheld controllers. Perhaps, instead of trying to add a new input, see if you can bind the controller’s buttons to emulate that of another controller, and name the axis appropriately as to avoid confusion.
I might be misunderstand your question, but other options are right there on the picture. Gamepad, PS4 controller, XBOne controller…