Trailer Tires Appear to be Out of Line?

When turning a double axle vehicle the rear does have to give a little as the front is closest to the pivot point of the hitch point. The inside of the turn tire(s) go(es) in and the out side of the turn tire(s) go(es) out as the sidewall flexes especially with radial tires. The other factor is the torque of the tires flexes the beam of the axle which is not stiff but a beam that allows the tires and wheels the opportunity to flex with it for turns and bumps and load weights. You do want to load correctly with 60% of the weight in front of the center of the two axles and 40% to the rear. The tow vehicle and the trailer do have to be within 4 inches of level up or down from true level of the two vehicles on one level plane. With all this the tire maximum load at maximum inflation, (in pounds), on the heaviest side should be inflated for the load,( maximum inflation for maximum load), and less for lighter loads. All other tires are to be inflated to the same as the maximum side, as weight shifts as roadways slope. Getting back to the axle beams, they are not to exceed design load and when no load they will be bowed up in the center and should level out when at max load. If the axle sags down in the center, it is either overloaded or designed to weak for posted maximum weight, and may need a stiffener added to them. Always check your lug nuts for design tightness.