If anyone was wondering where to find the games graphical preferences like I was. It's located in your AppData folder > Roaming > The Creative Assembly > Rome2 > scripts. This is useful if you want to change settings that the game doesn't allow you to change in-game. In my case I used it to turn off DX11 which got rid of some weird graphical glitches I was getting.
EDIT: It also allowed me to use the fast forward option in-battle. Which was an unexpected result, but whatever.