Of note, the "mod" that did this for DOS1 still works for DOS2, seeing as it's just an Autohotkey script.http://www.nexusmods.com/divinityoriginalsin/mods/47/?
I heavily modified my copy so that it also makes showing sneak cones a toggle, and performs a quicksave every 5 minutes. I also changed the key from Alt to J (because I wasn't using J for anything) so that it wouldn't cause any problems if it still thought the key was held down after exiting the program (although I did also add a timer to release the keys within 30 seconds of leaving the program). And I made it so hitting F12 would cause it to close itself (the script).
Here's my copy (notes are in the readme.txt):http://darkseam.com/Divinity_toggles.zip
It's not perfect, but it's better than not having it. Having the toggles programmed into the game would be much better.