I'm building a new 45degree character, who I want to be able to face either left or right. So I designed two hip sprites for either direction. But only the "Default" sprite will bend and warp with the character's movements. The secondary sprite just stays in place. 
It seems to be connected to the Hip bone, but not the Torso bone, so when the torso, head, or arms are moved, it won't go with them. But it seems connected correctly to the thigh bones. Could someone explain to me why the secondary sprite doesn't operate correctly, and how to fix it? Replacing the hip sprite seems like a useless feature if the replacement doesn't cooperate.

The secondary hip sprite won't work in this case unless you add new bones for it.
 


YouTube Tutorials Here

How do you apply new bones to an alternate sprite? I would do that if I were adding on an extra layer, but this I'm just swapping out the Hip in the sprite menu.

The problem with adding new bones to it is that it will not work with the pre-made animations. 


YouTube Tutorials Here

I'm still confused why and how I would be adding new bones. Shouldn't the sprite already be attached to the G3 bone structure? Again, I'm not adding additional sprites, I'm swapping out another sprite from the sprite editor.

Yeah. For unknown reason, it didn't work with the 'Hip'.
Adding new bones to the template could also make Window closed by itself. 
It worked before but not anymore.  




YouTube Tutorials Here

Oh, so there's no way to use both sprite switching and bone animation
on bending parts?

At the moment I have a 5 piece character and I want to switch the arm
sprite without an outline to the same sprite with an outline.

That just doesn't make sense!  You can do this in just about any 3D app
by switching  the texture on the plane you are deforming with any number
of bones.

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