On a future battlefield where mechs are somehow the most preferred weapon system (over the far more practical tank format), what kind of melee weapon is most effective?
From human warfare, we see the evolution of weapons from swords to morning stars to hammers. The reason for the evolution in weapons is that swords became less and less effective against plate armor over time while concussive hits by hammers proved to be incredibly effective. (Then there were guns but that's outside the scope of this question.)
Does this evolution hold true for giant bipedal armored combatants? Would an apropriately sized hammer be more effective in melee combat between mechs than a giant sword? If this does not hold, then why not?
The mechs in question range in size from 5 meters tall to 20 meters tall and 6 tons to 100 tons.
Based on this question about why mechs would use melee weapons over ranged weapons.