If I exchanged one grey cleaver by the second green one. My Question is: would the two green cleavers trigger each others infinitely?
no or else you could deal infinite damage with two cleavers
actually this was covered a few patches ago, cause it used to. now they only trigger eachother once, so green cleaver (gc) A is used by player, gc B gets activated, which activates gc A. But that 2nd activation for gc A doesn't reactivate gc B.