Just got to the rosters and scroll to the right to see all ratings.
But if you're looking for a 50/50 split this is NOT the answer. It's best to handle the substitutions yourself.
Personally to achieve this I have Stewart as the HB in my Pro sets, and Shotgun, and I manually sub in Cameron Artis-Payne into my Pistol sets to mirror what he ran at Auburn. For my scatback to get his 3-5 touches I manually insert him for the screens, sweeps, and tosses.
You have to do it each game, but it achieves the wanted results and isn't too cumbersome.