In GUIs, some menus use the bracket keys to cycle through tabs. In the controller tooltip, the bracket keys for this action are swapped.

Nope, the brackets aren't swapped, the left bracket is for cycling left and right bracket is for cycling right, if the key doesn't match the same one on your keyboard, there's nothing I can do, it's a GLFW problem

I dug into the .jar file for the mod and it seems that the left and right bracket keys are simply named incorrectly

Yeah that’s what I meant