Hulk can release bursts of Gamma Radiation.
Which going by the explanations on the profile, seems to naturally be CM type 1 hax (though someone should call a Marvel supporter to verify if it is combat applicable or not). Which would bypass Zamasu's regeneration and kill him and all his clones instantly through sheer range
Also, iirc, passive amps like Rage Power cannot be restricted, so Hulk could grow in strength up to 1-A, making Zamasu's clones a nuisance at best.
So, unless any of my reasoning above is wrong or Zamasu has some way to deal with Hulk, he stomps. Zamasu cannot BFR him as he resists it, and has no means to definitely kill Hulk due to his Immortality type 4. Meanwhile, Hulk's gamma radiation bursts would end Zamasu