Only a small TBB is needed to take out FTW.
Which still damages kurama, then hashi simply regrows it.
Full Kurama would blow up FTW, tank its smaller TBB without significant damage, then charge up a flash Bijuu Dama and it's GG Hashirama.
1. Gyuki's standard tbb forced him back into bee
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. Kurama's smallest tbb is his standard one which by scale would do a similar amount of damage. I don't see a reason to believe he would or even
could create a tbb small enough for him to tank w/ minimal damage but blow up enough of the forest as well.
2. There's still nothing suggesting he even knows what the pollen does, so he'd have no reason to blow up the trees unless they were attacking him. & FTW doesn't attack, it's passive.
3. When kurama gets damaged by the tbb hashi will know it went off due to his senses, if kurama tries to charge a flash tbb immediately after then the original hashi mayflies while he uses the clone to fix the forest in the meantime. Alternately, he can have the clone go right up to kurama & prepare to pin him or disrupt his charge time with hotei, he could even summon the rashomon gates to knock him back & cause the tbb to either
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or blow him up too.
Hotei hands still aren't catching or tanking flash Bijuu Dama,
Never said they would.
And Hashirama can't simultaneously be using Mayfly and FTW (wood clones would get blown up along with FTW).
How fast do you think kurama can charge a massive tbb? There's obviously going to be a charge time & naruto managed to
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. All the clone has to do is use hobi to tank the small forest-clearing tbb w/ kurama then he'll also be within range to disrupt any larger ones + regrow the forest.
Also from a kilo away & w/o sensory abilities how is kurama even going to properly keep track of the original hashi? If anything he'll think the clone is the original which allows the real hashi to avoid damage throughout the entire fight [one clone dies, he sends in another one from a different direction].
Also Mayfly is a really overrated jutsu.
It may be overrated by some hardcore oro fanboys who like to use zetsu's feats, but I'm using it reasonably here.
The blast radius of Kurama's charged TBB is huge and can reach Hashirama underground if the attack goes deep enough.
Mayfly has been used to travel distances such as from
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to
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, it's not a matter of going deep, it's a matter of avoiding the entire area.
According to the stipulations you gave a kilometer between these two. W/ the aid of his clone + his sensory abilities hashi will easily know when kurama is charging a tbb & if it's being aimed at his original body or not. If the tbb is aimed at his body then hashi has a kilometer's worth of time to use mayfly & travel the aforementioned distance before it reaches him. This should easily be achievable unless you believe the travel time of a charged tbb is faster than it takes for hashi to merge w/ the ground.