No, i am not underestimating Zoro's swordsmanship skills which i already can cut through Ribcage Susanoo, but what about Incomplete,Compelete, and Final Susanoo?Well basically your saying Sasuke can only beat him using Sharingan tech and Kirin?
You seem to be underestimating Zoro's swordsmanship Which could easily cut through a Susano'o ribcage.
Furthermore Zoro's Endurance is Inhuman and could tank a lot of Sasuke techs.
Also as to Kirin Zoro could just Observation Haki and then create a shield using Armament Haki.
Another point is the fact that MS tech requires a lot of chakara, and continue use would just burn Sasuke out.
In all honesty Sasuke's best chance at winning this is if the fight is a short one.
No, even with his Inhuman endurance....Zoro can't even withstand Amaterasu or Kirin.....Bee was able to tank his own Bijuuudama, but he was down in seconds with one Amaterasu from Sasuke...Bee endurance level is to tank Bijuudama(mountain buster attack), but yet he can't even survive Amaterasu for 5 seconds....what does that tell you? Bee's endurance>>>>>>>Zoro's endurance by a long a shot.
But this is not MS Sasuke....EMS takes much much less Chakra than MS.
How is Sasuke's chances short when Zoro as no way of hurting Sasuke? explain how Zoro beats EMS Sasuke?