Both movies are about first loves from high school that started as friendships. Both male lead characters become close with the girls even though they aren't consider "popular girls". Because of those friendships/crushes, the female lead characters grow in beauty and confidence. They remember their first loves fondly and hope to see them again.
Both dramas involve accidental time traveling and falling in love with a Joseon man. Splash Splash Love is only 2 episodes long, while Queen In Hyun's Man is a full length drama.
Both dramas involve accidental time traveling and falling in love with a Joseon king. Both also deal with former lives/ reincarnation. Rooftop Prince is a full length drama (20 episodes), while Splash Splash Love is a Drama Special (2 episodes only). Both also star kpop idol male leads (who are should be considered fantastic actors).
Both are about girls who are a bit out of place in their new environments and just happen to befriend and fall in love with rich and powerful people. Moon River takes place in a university, while Boss & Me is at a workplace.
Both are romantic comedies...but have drama in various episodes.
Both are romantic comedies...but have drama in various episodes.

