Hey,

Depending on which BT you have on Rinnesasuke, Kakuzu might actually be better as a pos 2 even if he is full BT. If you have Sasuke's Y+1 mystery and +2 passive (the one that scales with chakra absorption every round) then I'd use this team.

It would work better if you had Itachi 4 stars with his mystery BT (because in it's standard form it's not an instantly activated mystery), but with Kakuzu it shouldn't be too much of an issue either way, because you can just interrupt anyone who tries to stop Itachi setting up. Having Itachi's barrier for chakra benefits both Kakuzu and Sasuke since your chakra will be above 50 for Kakuzu's Y+2 mystery to be used back to back, and it will be above 70 so you can spam Sasuke's mystery too. Plus, scaling for them both.

If you don't have those BT on Sasuke and/or you want to run Kakuzu as pos 1 because he has all his BT, then I'd go with this:

I wouldn't use Sasuke's scaling passive on this team because it doesn't regain/generate chakra as reliably in round 2 and 3, and you want to have as much chakra at the start of each round because Kakuzu also relies on chakra to scale. So, I'd use Sasuke's y+1 Susano'o passive here. You can still use his Y+1 mystery because eventually by like round 4, if the match lasts that long you will be able to spam his mystery.

Hope this helps!