Patty and Selma - The Simpsons
Patty and Selma, Marge Simpon’s older sisters, are identical twins with different hairstyles who have an affinity for smoking way too much. They’re similar in that they both work Springfield Department of Motor Vehicle and have a distaste for brother-in-law, Homer Simpson, but differ when it comes to relationships; Selma craves male attention while Patty is a lesbian.
Sheldon and Missy - Young Sheldon/ The Big Bang Theory
Sheldon and Missy are fraternal twins and polar opposites. Missy is sassy and bratty with a cheeky sense of humor who is constantly fighting Sheldon for her parents’ attention. Unlike Sheldon, who is described as a 9-year-old genius with a "once-in-a-generation mind capable of advanced mathematics and science,” Missy doesn’t show much interest in schoolwork. Sheldon eventually graduates to the Big Bang Theory while Missy only appears in the first season and ten years later, for Sheldon and Amy's wedding.
Elena and Katerina - The Vampire Diaries
Again, Elena and Katerina weren't twins, but the dopplegangers looked so much alike, they could assume each other's identity with ease thus fooling even the men that loved them. There were actually a few more Petrova-dopplegangers, but Elena and Katerina were the most prominent. Katerina was manipulative and served as the main antagonist till the series finale wheras Elena was an honor roll student who struggled to live a normal life surrounded by the supernatural.