The issue of sway and weight relate to tongue weight of trailer and rating for vehicle. Search on this forum going back up to 10 years and you will get some great info especially about tongue weight. If the trailer has not been modified it is designed to be front heavy on purpose, never happened to me but I understand sway is usually caused by not enough tongue weight.
If the trailer is too light up front, no sway control is going to stop it. Check it out and please leave a comment to share what you learned for everyone else.