Previewing multiple Animation layers simultaneously in Edit mode?

I have a 2D rig with two Animation layers:

• one layer for foot-animation
• second layer with hands-animation

How can I preview them together in Edit mode?

-In Animation-window I can only choose one animation to preview at once - I couldn't find a way to preview two animations at once there.
-In Animator-window I could trigger the state machine to preview the animation, but the states only seem to play in Play mode. It would be very slow to jump between Edit and play mode all the time while coding and animating.

What is the recommended workflow for working with multiple Animation layers and previewing combinations of them together?

 

Also interested in a solution for this!

 

Timeline is the way to go, see my answer https://forum.unity.com/threads/checking-and-editing-multiple-animations-in-the-editor.1061906/