For the time being, I guess KGF has the edge because Chapter 1 is a huge hit in it's Hindi dubbed version and everyone is eagerly waiting for the second chapter just like all were waiting for Baahubali 2 after 'The Beginning' and we all know how that went.
As for RRR, of course it has Rajamouli as the director and two big superstars of South but still the film is entirely fresh. Ajay Devgn is there as a household name in Hindi markets but then again KGF also has Sanjay Dutt as the antagonist so, it should be a tough call and I am certain that the one that's better is ultimately going to win in the long run. But in terms of first weekend or week, I guess KGF 2 will have an edge.