Suggested by Sonic Greninja is a powerful fighter who has a lot of speed and that would be his best bet to try and secure victory here. That said, Itachi’s illusions should be more than a match for him here. Greninja would at least get slowed down by them a bit and once Itachi activates his sharingan abilities then it’s all over. Their physical stats may be comparable but Itachi has a ton of extra abilities at his beck and call that really allow him to dominate the fight. It’s hard to lose when you can do everything the other guy can but even better. Itachi wins.