Recommendations

Both are short dramas in which the FL is in a fictional story (tv drama vs. manga) and falls in love with the plot's villain.

FL is from a different world, travels to historical times, and meets the ML who is suffering from some illness she can treat/cure.

Modern day FL time travels to the past, falls in love with royal ML.
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FL enters the body of another girl and must live her life. Main couple clash/dislike each other at first, but later fall in love.

FL travels from modern day to historical times. ML is unique in some way (strange illness vs. being non human) and intrigued by the FL before he falls in love with her.

Both are lighter dramas with a FL who comes from a different world and enters the body of a girl who has died, taking over her life. ML is royal, suffers from some medical condition, and is initially antagonistic/threatening toward her, but she is the only one able to help/cure him. There is scheming within his family to replace/kill him.

Modern day/future FL travels to the past and falls in love.
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Modern day FL faints and finds herself in the past. ML seems cold at first but is intrigued by her and both fall in love.

Both dramas have a supernatural background and feature characters who can see the future. Kim Ji Suk acts in both dramas.

Both are remakes of the Korean original drama Voice. Both are following the original storyline closely.

Voice: 110 Emergency Control Room 2 is the second season. Characters are the same as in the first season.

Korean drama is the original and Thai drama is a remake. The storyline and characters are very similar.

Both films are, in their own ways, about one person trying to learn about the life of another person, who they previously did not know everything about. Both films handle this by showing us our main guy, in present day, meeting people and learning about the person through stories, and then, we, the audience, are shown flashbacks where we too learn about the life of the person.
Memories of Matsuko is about a young man piecing together the life of his now deceased aunt, who he didn't even know about beforehand, while The World of Kanako is about a father whose daughter goes missing, and as he doesn't have a close relationship with her, he learns about her from others and has to piece together her life in order to track where she's gone.

Both films are quite dark (World of Kanako is more unsettling and graphic while Memories of Matsuko is more tragic and depressing). If you've seen The World of Kanako, you can handle Memories of Matsuko, but if you're coming from Memories of Matsuko, please be aware that The World of Kanako is a lot more graphic.

In both dramas the plucky, outspoken FL ends up sharing a body with a weaker, more delicate girl who had an unrequited love for someone (ML vs. SML), and who eventually loses her life saving the FL. The lead couple initially dislike each other, but the ML becomes increasingly intrigued by the FL's behavior, leading to him falling in love, and eventually she loves him, too.

FL's spirit is in another girl's body.
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