Iron-Man = Iron-Monger (Iron-Man, but Bigger) Hulk = Abomination (Hulk, but Bigger) Thor =/= Loki/Frost Giant Guy (Wily Trickster...and a Frost Giant Guy) Cap = Red Skull (Same Superhuman Enhancement) Guardians =/= Ronan (Really Powerful Dude with an Army) Ant-Man = Yellowjacket (Ant-Man with Lasers) Strange = Kaecilius (Doctor Strange with Years More Training) Spider-Man =/= Vulture (Doesn't really have an origin story, so hard to say) Panther = Killmonger (Black Panther, but More Merciless) Marvel = Yon-Rogg (Captain Marvel, but weaker. Holy shit why is this movie so bad?)
Man, Marvel is really bad at villains in their origin stories, huh?
Having too many blatant evil counterpart villains is a comic book problem in general! Think of how many evil speedsters there are in Flash's rogues' gallery.