OK so here is a non FFB standing start in GT6, using a Lotus 97T, its not my video but reacts exactly the same as numerous ones I've put together before.
And here is a Lotus 98T in pCars
The difference in how the engine models the torque transfer to each tyre is quite clear. Its a simple test you can easily do, its best done with a controller as you can remove FFB from turning the wheel that way (after all if its modeled correctly it should occur with or without FFB). Red line the engine and either release the brake or dump the clutch, leave the steering alone totally. If it takes off straight and true with that much torque then its not being modeled, as you should get a torque bias to one side or the other resulting in rear wheel torque steer and a date with the armco.
That almost resembles the chaos at Imola today during the F3 race, quite a mess.