I don't think he'll be edo-tensei'd perse. But I think his second coming is Naruto. And no I don't mean "Naruto will become SO6P" I just think that he's already been compared to sage sensei by Kurama, and Kurama also thinks that He's the one to lead them down the right path.. No doubt about it Naruto is the second coming, or the moden Sage of six paths, I don't think He'll get rinnegan or the staff, I just think that he'll complete things that will go down in history and become mythical, similarly to the sage.