When wearing the Sage's Boots without any leg items on it deletes your feet, and if you wear them with a leg item the "socks" / below the knee portion of the leg model will clip through the boots.
easiest seen while crouching in third person. Male character, body type C
Attaching a picture of the "socks" clipping through the boots. Happens to my friend (female body type) and I (male body type).
It's more than this, Sage's Boots just deletes your legs entirely, even if you have no leg items equipped. Image attached.