2 Puppets Hands Shaking?

I translated Japanese into English with translation software.

1) Make two puppets.
2) Set each dragger behavior to "Limit range".
3) One is fixed after dragging the arm.
4) On one side, the arm returns to its original position.
5) Bring both wrists closer and the arms will move together.

YouTube

https://youtu.be/osFO0UaOpYw

Dropbox projectfile

https://www.dropbox.com/s/a48gl3gz3w0rro6/Hand_Shake%20.zip?dl=0

Thank you.