This is not right! Winny has an extra ring attached to the A-ring, and is completely different than primo. Furthermore, if you remove the 17alfa methyl, and add an ester to the 17 beta hydroxy, then you have something good, but that is like comparing boldenone with dianabol, so we are talking about something very different, and results are unpredictable.
Besides, if you just esterify winny without removing the 17 alfa methyl group (if that is even possible by steric hindrance), then your body enzymes cannot convert it to free winny, because the 17a methyl group is blocking the enzyme. So that would be a 100% inactive substance.