I have heard or peafowl/chicken hybrids, as well as guinea/chicken and guinea/peafowl crosses. Ive never seen one in person nor do know if they were real, but there are alot of strange things out there. But just because a peafowl is breeding with the chickens doesnt mean that they will be fertile. I mean I have ducks and chickens together and I always see the males mating with the other speices!
But if those eggs are free, I dont really see the harm in someone trying to hatch them out. IMO