Did you find any answers to your problem? I am currently having issues binding the inputs of the Cosmos in UE4.25.
Although my issues is I can’t get the thumbstick to work. I can get the button type inputs to work but not the thumbstick on the left or right controller. The thumbstick click to work (pressing straight down to click the button) but not the thumbstick directional movement.
I have tried a brand new VR template project and added all the HTC Cosmos inputs matching what the other inputs that were there for the Steam Controller which also has a thumbstick. Still nothing.
I am currently downloading 4.22 which I will try next. *Update - mapping is so different I couldn’t figure it out. I’m new to this.