I don't know if it is possible in dolphin directly, but you may be able to via glovepie. You'll have to learn some (ridiculously easy) code to do this, though. You may want to map the analogue controls to analogue controls through gloviepie, and this will be possible. If you need to know how to do this kind of stuff, download a wii muse script. Once you see that it's fairly easy to work out what you need to write to make it spit out what you want.
OS: Windows 10 64 bit Professional
CPU: AMD Ryzen 5900X
RAM: 16GB
GPU: Radeon Vega 56
CPU: AMD Ryzen 5900X
RAM: 16GB
GPU: Radeon Vega 56
