First of all, no. Not even a little bit. Heck, they're a focus of my collection. Secondly given all the plots in all the Transformer series, the very notion of a "Nemesis Prime" is barely a blip on the radar. While there are many, many black repaints of a Prime figure, very few are the "clone of the Autobot leader, paint him black, and flip the switch to evil" at that. A quick rundown: Black Lio Convoy: Real bad guy, 1 shot appearance. Black Big Convoy: Ultra good guy. He singlehandedly took on the Blendtron invasion stopping them before they could reach Cybertron. Car Robots Black Convoy/RiD Scourge: A ships captain, similar to Optimus Primal, Animated Prime, Lio Convoy, or Big Convoy who had been reprogrammed, then later reduced to drone-like status. Good, Evil, less evil. Armada Nemesis Prime: Bad guy, if not an avatar of Unicron himself then a lackey. Universe Nemesis Prime/Alternity Black Convoy: Starts off as being the kind of character you complained about, then later redeemed by Primus and one of the truest heroes. So, evil, now very good. Energon Grand Scourge: Evil. Not much is known about this guy other then he's more of what you were thinking of as just an evil repaint Prime guy. Nucleon Quest Superconvoy: Good. In fact it's just the real Prime in new duds. Alternity/Binaltech Nemesis Prime/Black Convoy: Well, he's just a character mess. Let's just say bad guy ultimately. Robot Masters Black Prime: Good guy. Again, it's the real Prime in new duds. G1 Black Prime: Another type that falls under the category that you complained about. Bad guy. Robot Masters Black Optimal Optimus: Good guy. Like his G1 black counterpart, same dude, new duds. Classics Nemesis Prime: Neither, yet. Could end up being a good guy, could be a bad guy. I doubt we'll ever know. Shadow Commander: Good guy, in a way. He turned on those who wanted him to kill defenseless beings and seeks a combination of revenge and his own freedoms. Of these 13 main repaints, only four of them are any type of variation on the "clone of the Autobot leader, paint him black, and flip the switch to evil" idea and one of those only started that way. Seven of them are good guys, so really only about half the time is a black repaint even a bad guy! This isn't true for just Primes either. Dark Skyfire, Override GTR, Sky Shadow and many others aren't evil counterparts but the same characters in a dark colorscheme or even a new friendly character in some cases.
RiD Scourge is a favorite of the 'category' for me, for a few reasons: . Not an "evil clone", at least not in a direct sense. Not RiD Prime/Fire Convoy in black, but picked up some of his features by scanning him along with the vehicle mode (been too long since I've seen the ep, so I don't remember if it was intentional or inadvertent) . The only 'nemesis' with an original mold to his name (Spychanger Scourge - Optimus Prime is the repaint of HIM! )