Blend Shape Presets Tool for Unity generates templates of blendshapes presets that can be shared between different characters that have the same set of blend shapes (ie: figures created using the same figure creation system). Dependent sub-meshes like teeth and eyelashes are not supported yet, but the author has promised to look into it.
“You can easily create facial expressions by combining multiple blend shapes into presets. Each preset is controled by a single parameter. So it’s easy to include the API in your game script.
“You can create different templates with variations using the same expression name, so you can create differences between characters without any line of code, just by changing the template.
“Another advantage is that you don’t have to deal with the original blendshapes names, you can use your own naming. If two characters don’t have the same blend shapes names, you can unify them with two template files (one for each character) using the same presets names.
Different blend modes are available : Blend, Min, Max, Override.
A “pro” version is also available with source code.