even if hashi doesn't know a perfect jin is possible he can still sense or recognize kurama's chakra when naruto ues it. remember bm and sage mode last for very short periods of time.
wood clone jutsu would really give naruto a problem because i don't think he'd be able to find the real hashi, hashi's poison trees are dangerous as well, his wood is very resilient i think it can protect him from most of naruto's techs. unfortunately we haven't seen all of hashi's jutsu but shinsu senju would pose a threat to naruto, the abilities granted by sage mode would probably allow him to make sage mukuton clones and because of the way he fights i think he can make many clones if doesn't move and just absorbs nature chakra.
sage mode greatly enhances naruto's and jiraya's techs so its safe to assume that sage mode would enhance hashi's wood jutsu since it would be made using sage chakra increasing its defensive and offensive capabilities
toad genjutsu is useless if naruto and the toads cant find the real hashi since there's no evidence that sage mode can be used to find hashi. also they don't know about his clone jutsu so naruto wont be looking for the real hashi he'll be busy fighting a clone. if they can find him and tell a clone from the original then hashi gets screwed by toad genjutsu
hahsi wins high diff without kyuubi because of shinsu senju, sage mode and the abilities it grants, wood clones, sage wood clones and wood jutsu enhanced by sage mode. with kyuubi he wins mid diff.
IMO naruto is close but not quite at hashi's level yet and since he cant go into km because of jutsu's like wood dragon his attack power greatly suffers when fighting hashi since he cant use multiple beast balls or even one for that matter. hashi on the other hand has the benefit of being able to absorb kurama's chakra. also its been shown that hashi can restrict peoples movement so maybe he can restrict naruto's movement for a short period of time.
can naruto differentiate between a wood clone and the original? this would be a key factor since he doesn't know anything about hashi's wood clone jutsu.
I think that since Naruto has spent so much time with Yamato he should know abt Hashi's wood clone (i'm actually pretty sure of that)
Naruto can sense people while in sage mode thanks to nature chakra, it's possible that he could "see through" Hashi's wood clone.
One thing I'm not sure, Hashi can suppress Kyuubi chakra but to which extent? We've seen Naruto breaking out of Hashirama's wood dragon performed by Madara (we dont't know if there's any difference in the techniques level performed by them but i don't think so, since Madara created Hashirama's forest while fighting kages on the same level). I don't think Hashi's slow but I'm sure Naruto's faster.
Naruto has huge chakra reserves as well so he's got durability and resistance to keep up with Hashirama. He could use multiple Odama Rasengan to get rid of Hashi's wood style (forest etc.). like stated before, genjutsu used by Ma and Pa is based on your hearing, no matter where are you, if you'll hear it you kinda f****d. Rasen Shuriken would probably be also useful to clear out Hashi's wood techs. I only fear that in fact Hashi would be smarter and he'd last longer after all. But still, Naruto has chances.