Morphle is tiny Blender add-on that creates an object containing shape keys of all selected objects vertices positions.
Installation: Simply download Morphle.py and install it in Blender: Edit -> Preferences -> Add-ons -> Install... When add-on is activated the Morphle! button will appear in Object Properties.
Usage: Select some objects, click Morphle! and in the World Origin the Morphle object will be created. It appears as an object with the most vertices from the selected ones. In shape keys of Morphle object you will find names of all previousely selected objects and can interpolate between their vertices positions. From then you can make instances of child object or spawn particles from Morphle's vertices, delete/hide polygons and edges, animate shape keys and enjoy your beautiful morphs.