In terms of stats:
• Speed
Kakuzu blitzed Kakashi, who by matching FKS Sasuke showed movement at V1 speeds. That puts Kakuzu at V2 speeds or close enough.
This is fairly flawed ABC logic and doesn't take into account of context from both battles.
Kakashi was already weakened from his training with Naruto prior to the battle with Kakuzu AND Hidan. [
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Sasuke was extremely battered from his fight with the entire Gokage. The Sasuke that fought against Raikage is nowhere near the Sasuke that fought against Kakashi.
Even the speed feat itself is questionable and only happened as a result of the situation at hand. Kakuzu only "blitzed" Kakashi due to him gimmicking him into thinking he was dead. Kakashi being caught off guard/surprise attacked doesn't constitute into a speed feat for the surpriser. There are multiple instances where characters have gotten "blitzed" by characters much slower than them because of a surprise attack. [
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The other time Kakuzu "blitzed" Kakashi was when he was already notably exhausted from having to deal with both Hidan and Kakuzu, as well as having to babysit team 10. [
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And even such, by the manga Kakuzu's speed isn't impressive. He failed to blitz an already pre-occupied Shikamaru. [
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His masks have even worse speed feats.
Fire Mask: dodged by IA Ino-Shika-Cho [
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Lightning Mask: Shikamaru was able to pull out a scroll and fully unravel it before it got the chance to hit him. [
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Wind Mask: The only mask to actually semi-land a hit. However it only did so because Hidan was pressuring Kakashi. [
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No real reason to assume this one would be stupidly faster than lightning or fire.
To make matters worse, the Fire+Wind mask, i.e his strongest combo was dodged by a notably exhausted IA Kakashi
point blank [
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Even in movement speed these things are pretty awful. Choji was able to not only perform jutsu before they reached him, but also place his palms down before they could reach Kakuzu. [
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Whereas Tsunade's speed feats come from synchronizing and simultaneously attacking in tandem with the Raikage. In speed Tsunade has Kakuzu beat left, right, and center. It's questionable if he would even get a single hit on her, let alone a hit that would do anything major.
• Strength
Kakuzu manhandled Choji and co with his strings and could knock down giant doors with his Earth Spear
Tsunade cracked a Hashi boosted V1 chakra armour, which probably scales to standard V3 armour in quality
So by such, I'm assuming you believe Tsunade>>>Kakuzu in strength?
• Defense
Kakuzu has Earth Armour which is hyped to diamond quality and is seen no-selling attacks from the Fire Cat Beast and Giant Choking
No-selling Matatabi is hardly a good feat in comparison to Tsunade's. Yugito Nii isn't a perfect jinchuriki. [
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]. Her transformation was hardly perfect just by the miniature size of it. Compare Matatabi here [
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] to how big her full bijuu's fist is here [
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]. Think of the comparisons as part 1 Shukaku Gaara. If Kakuzu's domu was nearly as strong as being able to protect from a full fledge biju, he would have absolutely mauled Choji when his domu made contact with him.
So they're pretty close. Kakuzu may have an advantage as he can cleanly tank her attacks, but to do so he must freeze him body so she's safe as well. Not many girls can say that around tentacles
Kakuzu will be tanking no such attacks. Kakuzu's domu being equal to V1 Madara susanoo is laughable. By pure power scaling Madara's defenses shit on Kakuzu's. Domu being anywhere near Madara's defense is headcanon and has no such feats to back it up.
In terms of abilities:
• Standard
Kakuzu has tentacles that are strong enough to bind a Choji, can cleanly pierce flesh and tank an FRS better than Armour Path.
Tsunade has her strikes which can decimate nearby ground within 20m
base Choji being someone leagues below Tsunade in terms of physical strength? I don't see how that's an accomplishment in this fight.
• Key
Kakuzu has his hearts who possess elements powerful enough to kill on contact,
Never killed anything on contact. In fact never successfully hit anything once.
with the Lightning Heart so powerful even an absorption scroll couldn't protect against it (according to Kakashi),
Kakashi never said this.
the Fire Heart incinerating trees on contact and the Wind Heart tearing the same apart. They can also be combined as per their elemental complements
Hallow, dead trees. Temari cleared a much bigger section of a forest in part 1. Hardly impressive considering Tsunade's durability far far exceeds the likes of trees.
• End Game
Kakuzu can take new hearts to stay alive. This mean that in the case of a double death, he can take a still beating heart from the opponent to save himself
The battle would never progress itself to the point where Tsunade would be on the verge of death, especially with byakugou up. If Madara w/ a killing intent couldn't kill her after hours, Kakuzu doesn't have a shadow of a doubt.
Even if it did magically get to that point, byakugou regrows Tsunade's heart should Kakuzu steal it.
Tsunade has a near endless vitality that allows for potent blindside strikes or can be used with Katsuyu to do a blindside Acid Spray
Katsuyu isn't even needed in this battle to be honest.
Again, they're close. Kakuzu has a slight advantage with standard abilities, since he's immune to her stuff. With key abilities, both are potent but Tsunade has a guaranteed win if she lands a hit. In end game, Tsunade still has better options as she could probably regen any heart Kakuzu takes and then use that to faint him.
Kakuzu isn't immune to her attacks. Just because domu tanked Choji's attack/an imperfect matatabi swipe doesn't mean he can no-sell Tsunade's attacks.
Tsunade is the perfect counter to Kakuzu. His entire arsenal is laughed at by Tsunade, and she has the caveat of regenerating herself to 100% instantaneously. Even if Kakuzu did do damage, he'd have to clearly one shot her in order to put her down, which isn't happening with his move-pool.