Both dramas are modern C-dramas that show young people finding their ways through life.
Both are in an office setting and show struggles that people face in their work, but also in their lives.
They take different perspectives, Remembrance of Things Past gives a more serious view, whereas Later, I Laughed has more comedy.
There are multiple couples and multiple important/interesting side characters in both dramas.

Both movies are set at the DMZ and are a military thriller. Both have elements of tragedy and brotherhood. The difference is in the story. Escape is focused on a North Korean soldier who wants to desert to the South, whereas Joint Security Area is focused on the events that happen between a group of North and South Korean soldiers.

Both movies are about North and South Korean soldiers who meet up at the DMZ. They are about friendship and brotherhood. Joint Security Area is a tragedy and 6/45 is a comedy.

Both are about a Japanese and a Korean who meet in Japan and fall in love.
They both depict the blossoming and struggles of love between people from different countries.

Both are about a man with skills to fight and investigate, receiving a position to combat crime. With a small team around them, they quickly learn how to use their fighting skills, quick thinking, and teamwork to catch criminals and fight against injustice.

Both are supernatural, both FLs need to atone for their sins by helping other people/souls, both have flashbacks to historical times, both MLs are at first unwilling to help, but ultimately do help and they both have a certain supernatural ability to help the ML. Both series have fantasy, a tragic past, elements of afterlife, boss-employee relationships, helpful people around the leads.

Both are a tragic love story with the leads having a reversed timeline. Both trying to cherish the moments they have together.
Both are beautiful, with delicate and meaningful moments

If you like both kdramas and cdramas and you like historical romance with time travel, then you might like both of these dramas.

They are different in story, but if you love tragedy movies based on real history, you'll love them both

Both dramas:
- High school cdrama
- Youthful, coming of age
- Leads go together to the same high school
- A group of 5 friends (3 male, 2 female)
- FL chases ML first
- Leads live near each other
- FLs have a very similar character
- More introverted/cold seeming ML, more clingy/cheerful FL
- Both adapted from a novel

Both dramas:
- are about moving back to their hometown after working in Seoul
- have MLs who love staying in their hometown
- are set in a seaside village
- have healing and romance
- have leads that had a connection when they were young