Reparent Mouth Rig to Different Character's Armature? My Question is whether anyone knows a relatively easy way to copy the mouth (rig and all) from one character's armature to another? They have identical topology, but different rigs (because I used Mixamo to get easy animations).

I want to move the jaw bone and all of it's children and associated mouth meshes from the black thin armature to the thick white armature. I have tried using the "Child Of" constraint and got the result in the picture below:


It seems like a step in the right direction, but I still don't see the jaw bone under the new armature in the Outliner Window. It is listed under the old armature's hierarchy. How do I get it to only be linked to the new armature's hierarchy now?

Edit: I've tried using the separate hotkey for the bones I want, but that makes them lose their mesh target. Any way around that?

Edit#2: Turns out I just needed to check the "Set Inverse" option in the Child Of constraint.

Edit#3: I've tried the ctrl+J shortcut to join the two armatures, but when I do that the mouth armature is translated into a massive version of itself very far away, and I cannot seem to find the mouth mesh when I do that.

Edit#4: So ctrl+J absolutely works!! You just have to make sure there aren't any constraints added to the bone group. So after I removed the "Child Of" constraint it looked correct! The last step was picking the proper parent in the new armature.

However, the mouth mesh that was originally attached to the old armature has disappeared. Any idea how to get it back?
I've discovered a way to do this without having to weight paint again.


In the Outliner Window, drag the mesh for your mouth to the other armature and set the Object as the parent. You'll see that the mouth mesh is still weight-painted to the old armature, but you won't be able to move it in pose mode (yet)
Make sure there aren't any constraints added to the armature from the mouth that you're trying to join to the new armature.
In Object Mode, highlight the mouth armature followed by the armature you want to join it with and hit CTRL+J to join them.
Select the bone parent in edit mode for the mouth bones you transferred over under the armature tab.
In Object Mode select the mouth and Shift-select the new armature and type CTRL+P and parent the mouth mesh to the new armature with empty groups.


That's it. You should now see your mouth has the same weight painting it once had but in a new armature! However, you may have to go into edit mode and translate it a bit to get it to line up properly with the bones.