In this battle where both are in-character, Ichigo would start with his shikai, but since he is not the type that underestimate his opponents he would try a blitz. Which wouldn't work on Zero, then he would do some sword duel, but soon he would notice that Zero is too much for him to handle only with Shikai, then he was going for Bankai. Now having the right-hand on AP and Speed, he was going to bliz Zero with a Gran Rey Cero Getsuga Tenshou (that amps even more his AP (since he's condensing his spiritual particles in his blade in order to release that pressure in a powerful attack), which probably would work this time. Zero probably was going to survive/avoid it, although I think he'd still taking some damage since Getsuga Tenshou is an AoE technique.
Anyways, after that Zero would have to face an Ichigo that could use Blut + Hierro to amp his defense considerably, can use after images to confuse him in order to get an opening for another GRGT and has a passive sense manipulation (
here) that probably was going to help here since Zero doesn't have any resistance to sense manipulation listed on his profile (Please correct me if I'm wrong). Now for Zero's Cyber Elves, he has to summon them, which means that they're not passive and requires activation, putting Zero in a bad situation because Ichigo probably would be constantly pressuring him in order to put him down quickly, which is something he always does in his fights. Ichigo was doing it against Byakuya and had a lot of kill chances in that fight, he just didn't kill Bya because he didn't want to, despite this fact he constantly pressured Byakuya to a point where it was hard for Bya to properly use his techniques against Ichigo.
To finish I'll be putting my points for both wincon's:
Zero can take Ichigo while he stills on Shikai, because Shikai Ichigo doesn't have the right-hand in nothing compared to Zero. However, I don't know if he would call his Cyber Elves right at the start, because I don't know how Zero usually fights in-character, but even when Ichigo fought against Byakuya he used his Bankai early there and if Zero waits for Bankai to then use his Cyber Elves, then it's the moment where Ichigo's wincon start to pop up
Because then Zero was going to be screwed up because he wouldn't have enough time, nor chances, to summon his Cyber Elves or to use his equip in an efficient way.
These are my reasons for Ichigo and that's why I'm tending to stick with him in this fight.
