They had it coded in once around 2007 or so, but it also allowed for hitters to be used as pitchers. But during beta testing no matter what they tried they couldn’t get hitters who had no pitching stats to be hit hard. You’d have Mark Grace and Ichiro throwing a no hitters every start... after a couple of months of tinkering, they shelved it with a goal of bringing it back in a future update. Never got much of a look after.
These days, with the new code, I’d imagine the could use 2020 Jordan Yamamoto as a baseline and just assign all hitters with no pitching stats Yamamoto’s line and take on a pre-determined penalty. That should allow us to play pitchers in the field and hitters with pitching stats as pitchers (Abner Powell, Tony Mullane and many others in addition to the ones mentioned above).