A great deal of reason behind why gymnasts look awkward and rigid when they dance in a gymnastics routine has to do with being taught to be square, even, level, balanced, tight, uniform, tucked in, hollow, etc.
It also has to do with your ability to stay on the beam. Gymnasts are taught to be square to the beam at all times for balance. Turn out means you have to turn back in to become square to the beam for a stable landing. Twisting out and back in again to land is a lot to ask and expect for a landing that does not wobble or teeter.
Turning one shoulder out or one hip out can also mean that your balance in the air drifts to one side. You cannot afford to have your floor exercise routine or beam routine drifting to one side in a pass.
You might need to lower your amplitude for a while until you get used to not turning your hips out. Only split as high as you can handle without turning your hips out. Then as you get better at it, then you can increase your split in the air.