In CA4 all characters are by default shown facing left. If you flip your character to face in the opposite direction (facing right) you will discover that all bone and face related features become reversed. Left becomes right and right becomes left. E.g. if you are in 2D Motion Key Editor, clicking on a right thigh will actually select the left thigh on the character. Same goes for facial features. You are clicking on the right eye in Face Key Editor, but it will actually select left eye.

I understand that it is not a bug; I think perhaps adding a flip option was actually an afterthought so perhaps it just slipped through the cracks. Either way I find it extremely confusing - to the point where it makes me dread it when I need to work with right facing characters. Ok, maybe not dread but reluctant for sure; in truth unless there is a lot of motion and facial feature tweaks that you need on your right facing character, it may not be that big of an issue, as the motions will translate correctly when flipped, but it is a nuisance nonetheless.

I understand that it might be a bit of an effort for the developers to adjust all related GUI elements but I hope that it can be addressed in one of the future releases.