Mold Breaker let's the opponent know it is in effect, so it will only catch an opponent that is not paying attention. Admittedly I am a victim of that. Un-Mega Evolved Mold Breaker EQ isn't something you can throw out safely since it is pretty weak and it can be punished. It's only comes into play with Rotom-W on the opposing team. Hyper Cutter only comes into play when the opponent has an Intimidate user: Landorus-T or Mega-Manetric (which you won't beat anyway). So both Hyper Cutter and Mold Breaker EQ are extremely situational: they only see use when A. the opponent has a certain Pokemon on their team and B. chooses to switch that Pokemon on Pinsir.
Moxie on the other hand can be applied to all of your matches. It adds an extra dimension to Pinsir as a threat: it can passively pick up boosts with EQ or Quick Attack. This can be incredibly handy in late game situations where you absolutely need to pick up a boost to cleanup. In the lategame, something maybe weak enough to fall to Quick Attack or Earthquake. Here is a tournament battle where that is exactly what happened (note QA does 4.1% min to ttar). Moxie overall is the most effective because it has the largest scope of battles / targets where it can be applied and its effects lasts through when you Mega-Evolve, i.e. the attack boost.
But then again, Moxie requires you to stay as normal pinsir for an extra turn which means you're stuck in the form of a NU mon.
I can then throw out a check or hazer to put Pinsir in a tight situation. I find that Moxie is also situational because normal pinsir is far from viable in an OU environment. However, Moxie does have the ability to change a game no doubt.




