If this is possible, please point me in the right direction for some information on how to get started. I would like to set up some hotkeys to toggle some values on the ini settings. Namely, I would like to be able to toggle a value such as bUseWaterReflections= between the values 1 and 0 by pressing a selected key on the keyboard without opening the game settings menu. Is this possible?

Why don't I just want to use the actual menu? It is immersion breaking, and it resets blood decals and grass distance every time that menu is opened, which I don't want to happen.

OBSE has a few commands to set ini settings from script (SetNumericINISetting/SetStringINISetting) in addition to commands for detecting key press, but I'm not sure whether those ini setting commands affect the running game or only the actual ini file (and works on reload).