Full knowledge for both.
Winner by Death or KO.
Scenario 1: Both can only stay in their base forms.
Scenario 2: Nero has access to Devil Trigger and Ishida can use Quincy: Letzt Stil.
Well Uryuu should be faster than Nero so if he keeps his distance he should be able to pull a win.
But I round 2, Nero should be protected from the arrows and have a better striking range plus loads of strength so I'll give it to Nero.
Can this guy dodge over 1000 arrows? I'm asking because I don't know.. Didn't play this one because no Vergil ._.
@WhiteLion: Normally no, he couldn't. I doubt he could even keep up with Uryuu on foot. But when he uses DT, a giant aura forms around him that should protect him and it increases his attack range and power greatly. It's kinda like Susano'o.
nero will get him eventually
@Stingerrain: Well Ishida has his thousand arrows. If he caught nero by some surprise arrows he will win.
Submissions can take several hours to be approved.