Dude, I already told you about this. Poster laminate, not the credit card thick stuff. YES, you can iron covering on your EPP wing. I've done it twice on mine. You can even paint on the laminate. It looks much better than the amateur graffiti look of spraying the foam.
You can use iron on film on foam planes.
The surface is not the best on foam but there are several ways to "prime".
"Paint" the surface with water-thinned white glue (aliphatic) is one way. Spray adhesive is another.
Remember to "overlap" the film as the foam surface is not the best even after priming.
Light covering film and low temperature is the best way to protect the foam from getting heat damages.
You can cover foam? I tried recently for a wing I was building with a friend, made from Home Depot pink insulation foam. It wouldn't stick, so I ended up using tape to attach it. On second thought that could be because I didn't take off the plastic covering first...