As long as the weight of the trailer is on the suspension, the trailer will move. The suspension flexes, the tires shift and give, also.
All those stabilizing add-ons help but at a price both in dollars and time spent setting up and adjusting. The folks who have gone this route are usually satisfied that they're worth the time and money, but even they will tell you not all movement is eliminated.
From what I've read on this forum, the folks who place bottle jacks under the frame fore and aft of the wheels have the best results; that's because they are unloading the suspension to a degree.
My wife and I just live with the movement. It's a travel trailer -it's supposed to move.