So why did we make it three Hokage against Kakuzu again... because for virtually anyone except for immortals with Edo Bodies, or God Trees that is basically going to the Hokage...
Anyways, Tsunade, Hiruzen, and Tobirama would win.... but it isn't like they walk all over him.
Doton: Domu is going to block any physical attack... this team lacks the Raiton to most efficiently deal with it. Hiruzen has the Staff, but at the same time, the minute he's engaging in close combat that leaves out any options for ranged attacks due to the risk of hitting Hiruzen. Despite even his age, Kakuzu has thirty years on the Third Hokage... he is also in a more physically fit condition, and his tendrils bring a greater versatility for CQB.... so it isn't like the Staff alone solos him.
Having his four masks he would have access to every the elements required to counter Tobirama (Katon + Fuuton, Doton), and Hiruzen (Raiton against his Earth... Doton to counter the Katon). Considering Shikaku labled Kakuzu a Doton style user, his final mask was likely a Suiton mask (because the concept of having an Earth Element with an Earth Mask is virtually useless). This means he counters Katon jutsu.
But I mean honestly... as this game goes on.... Tsunade and Tobirama have basically the same levels of Stamina as Kakuzu, between the three of them in terms of Taijutsu... it isn't like Kakuzu is an immortal invincible god of Taijutsu.
Let's try to make match ups that are actually fair fights. In one on one situations these are very good match ups.... but putting them together?! There's no point.
