In this Chess puzzle, your aim is to switch black and white, with a legal game, and arrive at the final position:
This aim is likely unreachable. So you must try to get the maximum number of pieces switched. Meaning your maximum score is 32 if all pieces are finally switched.
Please note that the pieces are switched, look at the Queens on the wrong squares for instance. In this final (impossible ?) position above, white King was, many moves before on e1 and all 16 pawns are one square away from promotion.
Finally, if two answers get to the same number of pieces correctly switched, I will favor answers with fewest moves. That doubly explains the