zeogold: Gadget, who, by some miraculous cartoon logic, manages to accidentally avoid everything.
Darvin: Gadget's ability to accidentally avoid all danger is so
consistent that it basically is one of his powers that must be accounted for in this analysis. Any direct attack against Gadget
will fail due to an apparent happenstance every time, and while Gadget will also fail either due to his own incompetence or a gadget malfunctioning it will never be in such a way that causes him material harm.
As presented, Inspect Gadget is functionally a supernatural foe with reality-bending power. Unless he's up against an opponent who is also supernatural, or is so powerful as to win in spite of every happenstance possible conspiring in Gadget's favor, he's basically untouchable. Or, put another way, if you challenge a cartoon goofball to a fight, don't be surprised if you get a cartoon goofball of a fight.
In that case, Robocop could hold Penny/Brain hostage until Gadget just gives up.
Really, the basis of what direction this fight goes in depends mainly on who's world we're working with, Gadget's or Robocop's. If It's Gadget's universe of cartoon physics, he might win since anything can happen. If it's Robocop's gritty, more realistic world where he's used to taking down the toughest of criminals, he blows Gadget to pieces.