Some of this material refers to weight distributing hitches.
These use torsion bars typically to shift weight to the front of the tow vehicle and can act as anti sway devices simultaneously.
There is also a large device that shifts the tow point to directly behind the axle, improving the physics tremendously.
These are hard to fit to anything smaller than a van or pickup.
My friend says to think of yourself as driving the trailer and not the tow vehicle.
I don't know if that helps, but it works for him.
He's the best driver I know, towing.
Also, it is not just the weight before or after the axle, but where it is located relative to the axle.
You don't always have a choice though.
I try to put the heavy weight as close to the axle as I can and just forward of it.
With my small trailer I try to put everything in front of the axle if I can, but this is well within the limits of the cars capacity.
Suspension matters on the trailer too.
My utility trailer has an anti-sway torsion bar suspension with shocks and the torsion bar may be tightened or loosened.
It has a spring which preloads.
This makes the trailer ride much more smoothly and increases the load I can carry.
I have pulled a trailer with a solid suspension and you don't want that.
It makes you realize how much work the suspension does.
That trailer could steer the truck in front.