You know not only that we know that Sakura will have a future role in the final battle, but Kakashi will also have a role as well. But just thinking of a battle plan won't be much help in this fight so what else can he do??
Well.......why not have both of Obitos sharingan eyes?? O_o
Black Zetsu seems to be leeching off of Obito so we will probably be seeing Obitos last moments soon :(. So before Kakashi goes back into battle maybe he'll ask naruto to give Obitos eyes to him.
If naruto can bring back an eye out of no where then I'm betting he can make it to where kakashi's eyes transform into Obitos sharingan (like a regular Uchiha can).
So if Kakashi gets both of Obitos eyes he can...
-freely use Kamui how ever he can
-make himself intangible
-teleport himself, other people, objects or attacks in double the speed then he originally had with one eye
He would Definetly be a great asset in team 7 teamwork when fighting kaguya's power
Unless of course Kaguya can somehow cancel out chakra as a whole, rendering any technique useless.