My reasoning on why I think Zoro could possibly break out of a genjutsu
By Genjutsu I mean like normal Genjutsu Itachi used on Naruto and during the fight with him Kakashi Sakura and Chiyo
and the fight between him and Sasuke.
I believe that Zoro could potentially break out of the Genjutsu because Zoro isn't new to illusions due to his most powerful move/attack Ashura or asura because he brings in 2 more versions of himself holding yet another 3 swords which turns into 9 sword style
It's clearly stated that his 9 sword style is an illusion when we are first introduced to it thanks to Kaku.
Maybe Haki has to do something with him creating Illusions like how some shinobi have genjutsu jutsu's
Which comes to if Zoro can create illusions he can potentially break out of one.
Then there's Infinite Tsukuyomi and kotoamatsukami which I doubt anyone can break out of especially Infinite Tsukuyomi
But I think Zoro could withstand Tsukuyomi the one Itachi used on Kakashi during OG Naruto.