Both are short dramas that start out light and fluffy then get more serious toward the end. The ML has a more sinister, darker personality trapped inside him that is trying to take control and who the FL is trying to save him from. Both FLs are from modern day and have traveled back to ancient times where they met the ML. Both FLs have some form of magic and are connected to the ML in a supernatural way. The ending is open but the two reunite in some way in modern day.

Lighter tone, short, and enjoyable dramas with an adorable FL who travels from modern times to a historical setting, meets the ML and falls in love with him.

FL travels from modern day to historical setting, meets and falls in love with ML. Both are fluffy, light dramas with a quirky and adorable FL.

Historical set, breezy dramas. In both the ML has been poisoned (although it doesn't affect his health, only his senses in YSMD), and the FL is the only one who can ease or cure his condition which results in the two living/working together.

Both are short, fluffy historical set dramas with a poisoned ML who can be helped/cured by the FL.
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Fluffy dramas with the main duo solving crimes, conspiracies, and mysteries in ancient China. The main characters' relationship is somewhat antagonist, with one forced to work for the other.

Both are fluffy dramas about a duo solving mysteries and crimes in ancient China.
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Both feature a crime-solving duo with supporting characters.
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FL "dies" and comes back in another girl's face/body. FL is a strong, intelligent, and clever character who takes revenge upon those who wronged her. The ML is a good fighter with the FL his weak spot. Both are historical setting and part of the plot revolves around a plague outbreak with the FL attempting to find a cure.

While different in plot and tone, both feature a FL who ends up in another girl's body and lives under her identity with her family. The ML has a secret, darker identity than the persona he seems to be. Both are short length dramas.

FL transmigrates to another girl's body and assumes her identity.
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FL finds herself in an arranged marriage with the ML that turns into genuine love. The ML hides his true identity/personality behind a different persona (pretending to be a eunuch vs. pretending to be unintelligent).