X-leg: When the leg is naturally straight or standing, the knees can touch each other, but the medial malleolus of the foot are separated and cannot be brought together.
O-leg: When the legs are naturally straight or standing, the inside ankles of the two feet can touch each other, but the knees cannot be close together.
It is impossible to tell what kind of leg it is just by walking outside or inside. I hope it can be adopted.