Iron Man's greatest Marvel Comics adversary made his second MCU appearance in What If…? season 2, but the infamous villain never got the chance to battle Robert Downey Jr.'s Tony Stark. Downey Jr. debuted as Tony Stark back in 2008's Iron Man, Marvel Studios' first MCU project. As well as introducing the future armored Avenger, Iron Man also teased the debut of one of Marvel Comics' most sinister villains. While Tony Stark went on to battle Obadiah Stane's Iron Monger, Justin Hammer and Ivan Vanko, Aldrich Killian, Loki, Ultron and the Mad Titan Thanos, the MCU's Iron Man never got the opportunity to go toe-to-toe with his Marvel Comics archenemy.
https://screenrant.com/iron-man-mcu-nemesis-wenwu-never-met/