It turns out that one can sand and shape EVA foam quickly and easily with a Kutzall file and carbide sanding mesh. Save your money and save your lungs by hand shaping EVA foam.
In this video I used a fine warding file shape:
There are more coarse versions and half round shapes etc etc. Feel free to try them but to be honest the ‘Fine Warding’ file is the one I have and it serves all my needs.
The sanding mesh can be bought here:
There are a ton of options to use. Start with 80 grit and work your way down to a nice finish.