#2 Cesaro
After winning multiple tag team Championship all across the globe as part of The King of Wrestling alongside Chris Hero (Kassuis Ohno in WWE), Cesaro made his WWE debut on April of 2012 as a heel and would capture the United States from Santino Marella at SummerSlam of that year.
This would be his only singles Championship run in the company till date as the Swiss Cyborg hasn't been to capture any major singles title ever since losing the US Title to Kofi Kingston on an episode of RAW in 2013. Cesaro has tasted success in tag team competition with multiple partners.
First, he won the WWE Tag team Championship with Tyson Kidd and would then form an alliance with foe-turned-friend Sheamus in 2016 with the duo collectively known as The Bar. The Bar has become an integral part of WWE'S tag team division. Despite being of one of the best in-ring performers of this generation, Cesaro was never given a chance to prove himself as a singles star by the WWE.