A River Runs Through It (2021)

Both are set in the late 90s/early 2000s and the stories span over highschool, university and adulthood

Very different setting/plot but similarities in characters.

ML has a more unusual personality (more like a SML). It's not obvious at first who FL will end up with as she initially loves the other male character. FL is optimistic and very romantic.

School setting. Themes of nostalgia and growing up. Main couple support each other even before they're couple. Happy endings.