Chronologically speaking, Zoro needs to beat Mihawk before he fights Nasujuro.
Says who?
Nasujuro being above Mihawk
An impossibility due to Mihawk's title.
Mihawk is the World's strongest swordsman, Nasujuro is a god. A god being above a swordsman is only natural.
Zoro is a God too, since Enies Lobby... Is he above Mihawk because of it?
I have no obsession with Mihawk being Zoro's last fight but your reasoning is simply flawed.
Nasujuro is as much of a god as Ryuma was - neither of them is a god. It is simply a reference to the planet's name.
Who said WG fights are last?
Oda said the manga ends when the treasure is found, not when Imu is beaten.
Using Marineford as a blueprint, WG war is just another opportunity for Teach to score another Devil Fruit.
Mihawk's title places him above anyone with a sword, it is that simple. Nasujuro cannot possibly be stronger, this is just Shanks v2...
The God titles mean nothing. Luffy is a god too, plenty of people stronger than him, even those are dont have God titles.
Mihawk - Build up - Baron
Mihawk - Sword - Baron
Mihawk - Title - Baron
Mihawk - Timeline - Baron
Mihawk - Relevance - Baron
Everything favors Mihawk, from the introduction and thus a longer build-up by a 184 chapters, a superior sword due to having the strongest blade, a superior strength title with
World's Strongest, coming after Baron instead of before as you assumed to finally being a far more relevant character who is the true Power representative of his organization and one among only 3 characters in the world being representatives of Power compared to Baron who is just one of Imu's 5 trusted supporters...
In the case of WG happening last, someone else will show up to be Zoro's last opponent and Baron will be a warm-up.