I can give a great list of genjutsu user capable to create the reality genjutsu that some people mention concerning Itachi including genin or chunin level ninja. It seems not to be a great of a feat, but like against every genjutsu, the one caught in one must be careful enough to identify the genjutsu if he were caught in one
To date the only ones Itachi really fooled with this type of genjutsu is an unexperienced 10yo Deidara who never fought in battle before(databook) and Naruto who was inexperienced in the genjutsu art as well, but when you watch the fight carefully, you'll realise the finger genjutsu Itachi made was too damn obvious to notice. It's only that Naruto was the one too slow to realise. Since the start we see Kakashi and Sakura turning into Itachi clones. A smart and careful one would have realised it was a genjutsu since that moment. It's only Naruto who wasn't good enough to realise until some point later
Generally infact the reality genjutsu Itachi create aren't difficult to notice since he almost all the time turns himself into crow. Killer-Bee a much experimented ninja did recognise it the second he turned into crow. I've no doubt in my mind Tsunade would as well
Now there is Itachi's kanashibari no genjutsu that he used on Orochimaru. This one isn't used to fool but rather immobilise the opponent. But this genjutsu is better suited in a close situation since it's in this range that it gives Itachi enough time to intervene. Now it would depend on Tsunade's reaction time here. Maybe she would simply do like Kurenai did in part1 to break free from this genjutsu the second she is caught in it
Btw, Orochimaru didn't really lose to Itachi's genjutsu alone since after Itachi cut his arm, the genjutsu broke because of the pain inflected by the attack so at that moment Orochimaru wasn't defeated especially when you know he possess a switching body capacity, and let's not also forget Orochimaru was only there to take his body and Orochimaru uses this technique only when his body starts rejecting him, so was probably at his weakest as well
So besides the fact that ABC logic doesn't work, i don't think Itachi could have defeated a full power Orochimaru with 3tomoes alone. I even think that they fought more than what it seemed to be because Itachi recognised Orochimaru's yamata no Orochi, as well as his special kawarim when either he or Sasuke used it during the battle against Sasuke, which means he saw Orochimaru use those techniques probably during that battle