This is not correct. Sensor size just increases the field of view, it doesn't change anything in relation to distortion. The glass will have the same properties regardless of what sensor size/caemra it's on. You may misunderstand how this all works.
Let's say you are standing at point X, with a 50mm lens on a cropped sensor camera, and have your subject at point Y- and that photo allows you to see the subject from the waist up. If you dont move point X, and put that 50mm lens on a full frame camera you will be able to see more of the subject now, maybe to their knees, due to the field of view expanding, but the lens distortion does not change. Going to full frame is just expanding the field of view of what the lens was already seeing.
The issue that you may be referring to is, if you want to get the same rough composition, aka see the subject from the waist up. You would either - not move from point X, and put lets say an 85mm lens on the full frame camera, OR, keep the 50mm lens on the full frame camera and change your point X to be standing closer to them. Both of those scenarios are changing distortion due to how close you are to the subject in relation to composition.
In summary- the human eye is closest to 50mm regardless of camera and sensor size.
That may have been confusing but I hope it helped.
