Zombies have been thrown into every other scenario, so why not World War II?
In FUBAR, Volume 2, the "what if" involves soldiers in the Pacific Theater fighting not only each other, but a host revivified corpses.
Though each tale only takes a few pages, I found the premise just kind of silly and tedious, and the artwork was not particularly inspired. If you're into the genre, you're better off with the much superior "Walking Dead" series of graphic novels.