Complex 2D animation rigging I want to animate a few custom characters. They need to be 2D. I have all body parts individually (PNG files) parented to the 3D meta rig at the corresponding angles. I have front, quarter-turn, and side view. I wuld have no problem if I was allowed to use separate bone structures for the same character. I have been key framing the alpha fade parameters to hide unused assets when rendering. The biggest issues I have are the toggling between eyes and mouths on each character.

I have a separate rig for the mouths using UV mapping technique and sliding a bound obj over a map of the mouths. When I have 2 or more mouth rigs in a scene, the rig glitches and doesn't render. I just copy the rig when 

For the eye rig, I have one asset for the different eye colors and a separate one for all the eye lids for each direction the character faces. I do not know how to set this up.

All tutorials I have access to say I must redraw all assets in Grease Pencil then manipulate them. That would work, but I already have the assets made by an artist.

I have both blender 2.79b and 2.8 beta.
i hope, i understood problem (not sure), For toggling eyes / face etc.


you can create a simple property to control, which elements (meshes) you wanted to show / toggle.
i.e > add a property on a control bone. assuming default name is 'prop'
now, for example, you want face side (v1) when prop is 1 and face front (v2) when prop is 0.
in blender 2.8 setting up drivers is pretty fast / easy. 


right click on property and copy as new driver
select face side , in object viewport display setting, right click paste as driver
select face front, do same as above step 2.
try changing property value, both objects will hide or unhide (don't panic)
select one of them, edit driver, change 'average or sum' to 'scripted' and replace expression '0 if prop==1 else 1'



select ground plane and change prop value in side bar (to test). i hope this helps.
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