UX design and visual design have many overlapping principles.

However UX design mainly has to do with how things work where UI design has to do with how they look.

I build wireframes and prototypes and user journeys and flowcharts and create interactions for apps and websites. I just don't do the visual part. But symmetry repetition proximity alignment are all a part of it too.

No one would expect a visual designer to create flowcharts or user journeys or interaction notes on how something should work.