I'm playing on Stadia as well, and I have the same issue. Additionally, there are several hotkeys that I don't seem to be able to be set. For example, despite trying to assign the "Go to camp" button to keys I was able to use for other inputs, I can't get the "Go to camp" input to register. This happens with many of the inputs in the game, and I consequently have to use the mouse to utilize much of the game's functionality. I assume these two issues are related, but both are pretty substantial QoL problems. I'm also curious if our inability to utilize certain keys, like F keys, is a related issue.