vidi (3/27/2021)
I spent 3 hours in Blender fixing the 3 main morphs (Blink / Blink_L / Blink_R) and of course not a single eye look the same once morphed now,
Easy tip if you have Zbrush , maybe Blender has similar tools, I don't know.
Import the Default open Eyes Mesh in Zbrush, store this additional in the Morph panel.
Use Symmetry and close both Eyes with the sculpting tools.
Use the ZMorph brush to open the eyes separately (Morph back)
With this method you get exactly R and L Close Eyes in no time
Easy tip if you are paying a Zbrush subscription and actually know how to use Zbrush :)
Don't take it badly, I know you're trying to help and I'm sure this process is extremely easy for someone who can handle zbrush... but yeah in the case here we would just like a really easy solution that doesn't involve a thousand (expensive) external tools.
A Video tutorial with Daz/CC even 3DXchange could be nice. Worst case with Blender (as it is free)