Scott Lang or MCU, despite making his first appearance 5 years ago. Although his films have been liked by fans and critics, it's fair to say that they haven't garnered massive fan followings like other new, successful franchises, such as the Guardians Of The Galaxy films.
However, Ant-Man allowed the MCU to execute another less serious superhero movie, and Scott Lang's backstory is intriguing, to say the least. He also developed a cute and hilarious relationship with Hope Pym. However, if Hope had remained frosty towards Scott, then who else could Ant-Man have ended up with?
Natasha Romanov (aka Black Widow)
Natasha Romanov has been part of the MCU almost since the very beginning. She first appeared in Iron Man 2, the third film to be released as part of the MCU and while her character didn't have a large role, she got plenty more screen time and development in the first Avengers movie.
However, she and Ant-Man didn't officially meet until Captain America: Civil War, when they were on opposite sides of the warring Avengers factions. They were pretty evenly matched and given that they were opponents, they appeared fairly civil to one another.
Carol Danvers (aka Captain Marvel)
Although Ant-Man and Captain Marvel never officially met (despite both of them having survived the Snap), we think they'd make a decent couple. Carol Danvers spent a lot of her twenties fighting alongside the Kree, an alien species at war with the Skrulls, and subsequently, the rest of the universe to boot.
However, when she returned to Earth, first in the 90's and then again to help out the remaining Avengers, she was firmly on the side of humanity. She would have curbed Scott's 'enthusiasm' and he in return could help her to understand her powers with the help of his friends.
Jane Foster
So far, Jane Foster has been a divisive character within the MCU. In her only appearances (so far) in the first two Thor films, she basically acted as a love interest for Thor and that was about as relevant the character ever got. She had no personality other than she was in love with Thor.
If she had met Scott Lang instead, perhaps her character development would have been different. Thor himself was played fairly straight in his first few appearances in the MCU so coupling up with Ant-Man could have resulted in Jane developing a sense of humor and becoming a well-rounded woman.
Wanda Maximoff (aka Scarlet Witch)
Scarlet Witch is probably one of the most powerful characters in the whole of the MCU (apart from possibly Captain Marvel), but we haven't yet seen her use her powers to their full potential. She also hasn't had much luck in the dating department, with her recent love being murdered by the Mad Titan, Thanos.
Fans weren't sure what to make of Wanda and Vision's relationship, as it seemed sort of shoehorned in the third film in the Captain America franchise. However, had Wanda ended up with Scott, their relationship would probably have been a lot happier, and a lot more fun.
Mantis
We're going to be honest, a lot of the entries on this list are from the Guardians Of The Galaxy franchise, as it and the Ant-Man movies are incredibly similar in tone. Therefore, we think Ant-Man would make a great couple with many of those characters. However, we've started with Mantis.
Mantis is a fairly recent addition to the MCU, having only first appeared in 2017. However, she has made a lasting impression on fans. This relationship, in particular, would bring out Scott's goofy side, as Mantis lacks understanding. This couple would simply be a joy to watch, and they'd care about each other too.
Jessica Jones
Jessica Jones is quite possibly the fiercest woman alive. Endowed with amazing strength, and a gifted detective to boot, the only thing that Jessica lacks is a warm personality. Through no fault of her own, Jessica is severely emotionally damaged when we first meet her in her own solo series.
Kilgrave, Jessica's mind-controlling nemesis, took control of her for a long time until she eventually broke free, leaving Jessica unable to fully trust anyone. Scott would be incredibly sympathetic to her plight, but he also wouldn't let her wallow and would encourage her to laugh a little.
Gamora
Pairing Ant-Man up with the daughter of Thanos can only be a recipe for success. In her first appearance in Guardians Of The Galaxy, Gamora was an intergalactic assassin who worked for her adoptive father, killing thousands in his name. However, she then redeemed herself over the course of the film.
Gamora was one of the few serious characters in that franchise, due to her abusive relationship with Thanos. If she and Ant-Man had become a couple, he could have helped her realize what true paternal love was, as Scott has a daughter who he rarely gets to see but clearly he loves her very much.
May Parker
If you aren't familiar with the MCU, and only know of Aunt May from the previous Spider-Man movies, you might be a bit disturbed by this entry. Fortunately, within the MCU, there is only a 5 year age difference between Paul Rudd (Ant-Man) and Marisa Tomei (May).
May is still Peter's aunt and she is aware of her nephew's hero persona and she appears to be extremely ive of his crime-fighting antics. Therefore, she would make a great girlfriend for Scott Lang, and she'd also keep him in check. She'd also be such a cool mom to his daughter, Cassie.
Nebula
Nebula's situation is similar to that of Gamora, except when her sister realized that Thanos was insane and evil, Nebula still insisted on serving by his side. However, Nebula secretly resented Thanos for always favoring Gamora, and she soon became disillusioned by his endgame, much like Gamora.
If you thought Gamora was serious, Nebula takes it to a whole new level. Before Avengers: Endgame, Nebula's default setting was grumpy. Nothing made her smile and she was reluctant to display even the tiniest emotion. Scott could help with that as he has a gift for winning over even the most cynical of people.
Valkyrie
Officially the MCU's first LGBTQ+ superhero (it was a long time coming), Valkyrie has only made two official appearances in the popular movie franchise (so far). However, this was enough to make fans and critics adore her for her tough, no-nonsense attitude and her hilarious sense of humor.
Scott and Valkyrie are basically perfect for each other, as they both know what it's like to lose their friends and family to an unstoppable force, and yet they keep ongoing. They've also got a great sense of fun, which compliments the other just beautifully. These two really do deserve their own ship.
