Vargas by decision. Joppy's size edge isn't enough to compensate for Vargas being the more talented and more skilled of the two. Plus, Joppy isn't a big enough puncher to crack Nando's chin.
As much trouble vargas had making weight there is a reason he did not fight at Middleweight. He is not able to hurt Joppy but tires himself out trying to do so. Meanwhile Joppy's work rate and stamina win him rounds. Very possible. Joppy had a good chin. Why do you think Tito wrapped em extra heavy that night?
Joppy and Vargas are about the same size. Prime Joppy is a tough fight for Vargas. Vargas hits harder and is more skilled but he's slower and more deliberate. Joppy was scrappy, durable and very active. I think it would've been really entertaining. Vargas close decision.
Vargas slower than Joppy? No. Vargas wasn't slow. He just wasn't super fast, and had trouble with fast handed guys like Tito, DLH, and Shane. But Nando was slow, he had good quickness in his prime.
Vargas may not have been slow, but he wasn't that fast and he was deliberate. Joppy is quicker and more loosey goosy. He can touch Vargas or make him react as Vargas prepares his next tactic.