Found that putting shorts over leggings results in this.
Viewing post in Bug Reports
Hello! It looks like that is caused by tanktops instead of leggings. Tanktops are placed in a layer below other clothing (pants/t-shirts). To fix this problem, you can switch to the tucked variant of tanktops which are available. That being said, looks like we need to add tanktops that are placed in the same layer as t-shirts, so the untucked variant will properly show outside pants. Thank you for your information!