Tobirama wins this high diff
--MS techniques wont hold much weight here, sensing enables tobirama to fight without eye contact, and with clones here, the probability of him getting caught in genjutsu diminishes even more, added to the fact that he has immense experience in fighting the uchihas so him getting caught isnt happening
--amaterasu is non factor its sensed, and reacted and evaded by FTG with ease
--susanoo is not catching tobirama here, ever. he dances around its attacks on foot, added with clones, FTG and marked weapons means that he eventually tags it and teleports itachi out of it, allowing tobirama to mark him which is an instant KO, Tobirama teleporting right infront of susanooo and prepping GKF also helps him bust open all susanoo bar V4.
--CQC is probably the worst thing itachi can do here, when Tobirama is not only faster than him but has the assistance of FTG which helps him either evade all of itachis attacks or land one touch on him which as mentioned is the end for itachi
reason why this is tough is because itachi is not letting tobirama come close to susanoo that easily nor are any of tobiramas attacks even puttting a dent on armored susanoo, his crow fients and finger genjutsu can be very easy to fall prey regardless of tobiramas intel on genjutsu and uchihas. outlasting itachi is also not cutting it due to him being an edo
