I know others have done it, and the foam would be covered with Bondo or (
serenko3 what's that other stuff called, I can't remember) first...
Covering EVA foam with Bondo will not end up working. One of the primary reasons people use EVA foam is its inherent flexibility. Bondo or other automotive body fillers dry extremely rigid, almost brittle. If you put Bondo on top of EVA foam, the first time the foam flexs, the Bondo will chop or crack off.
There are some products from Smooth On that I am lead to understand can harden and increase the rigidty of EVA foam, however those will be specialty products available only from that company, and I can not speak to their use, as I have not used them myself.
As for automotive paints, there are several different kinds available. There are some automotive paints that must be heated to be set, but automotive stores also sell "rattle can" varieties that work like normal spray paint, there are also air brush varities of automotive paint as well.
Both the rattle can and air brush types of automotive paint should work just fine with EVA foam, as long as it has been properly sealed with plasti dip, or mod podge, or another method, and you understand you might be in for constant touch ups if the paint flecks or cracks as the fian flexes.