From a GVWR perspective no. Nothing you do will change the rated cargo carrying capacity and everything you do to beef up suspension or anything else will likely eat into your rated CCC. That said, many people upgrade axles, leaf springs, etc., to improve handling and capacity but overloading is overloading. Modest overloading will likely not create adverse issues but no guarantee. It's better to select a trailer that has adequate CCC from the start. Adding shock absorbers can help with dampen bouncing (up and down motions), Sumo Springs can help dampen downward motion, heavier leaf springs can help alleviate springs from flattening out and stiffen the ride a bit. But all those suspension upgrades cannot reduce the added stress on weak points of the frame if significantly and consistently overloaded.
I say this as someone who knowingly runs near capacity generally and occasionally overweight by up to 500lbs depending on how much water is on board in the various tanks. 17,000 miles on my unit so far and no problems, but that doesn't mean I won't have issues down the road.