i have never tried this but you might also be able use vinyl wrap on foam
this forum explains it
https://www.hobbysquawk.com/forum/rc-airplanes/rc-model-tips-and-tricks/77821-vinyl-wrap-for-foam-planes
when I'm covering foam wings i use this.
https://www.amainhobbies.com/top-flite-monokote-clear-6-topq0200/p609819
i keep the iron on low heat when covering