As for sway if the trailer has any sway without sway control under normal towing do not tow.
Fix the sway problem. Most common cause is low tongue weight.
Sway can also be caused by nose high trailer, tow vehicle wheel alignment, trailer axle has tow out (should has about 1/8 to 1/4 inch tow in. Trailer axle not square with center line of trailer. Trailer axle camber and a bad trailer tire (broken steel belt etc)
Mis adjusted brakes on trailer.
After sway has been corrected then I would recommend a friction sway bar if you are not going to use weight distribution. This gives added control in emergency pedal to the metal braking and large trucks that pass close at 40 mph faster than you are going.