The wii remote is a very unique device, not only does it have accelerometers in it, it also relies on another device, the sensor bar, to know where it is in relation to you. To add support for such a device is not trivial at all and honestly not wanted or needed by most Bigbox users. Although as stated there are 3rd party apps that could help you, there is a reason that pretty much only the dolphin emulator supports it, it's unique and difficult.