Oh! My Sweet Liar! (2020)

Both are historical dramas. Both of them involves marriage at background and a noble male lead and ordinary female lead.

Based on the info in hand:

Bubbly FL
Prickly pear like ML ; hard on the outside but soft inside
ML and FL slowly getting fond of each other
Sweet - treats in dramaland

Both dramas have a similar feel, with a FL who is lying to the ML and ends up forced to live or work with him while hiding her secrets. Both couples are an enemies to lovers relationship, with the FL initially disliking/afraid of the ML who seems cold and harsh at first.

Paen Rai Long Tai Wa Rak is modern, but both the female leads pretend to be pregnant to search for clues. Both are comedic and the ML's families are welcoming to the FL.

Despite the plot differences (no face swapping), the dramas have some similarities, albeit small.

The main similarities:
•The male leads are generals
•The female leads are painters
•The relationship is slow but trusting, the ML will steal your heart

The amount of episodes and their duration are longer but it's worth it. You may need to have patience with the FL and the particular storyline but you might enjoy it. Give it a try!

FL finds herself unexpectently married to the ML in an arranged marriage. She is not the person she appears/is pretending to be. The marriage ends up turning into true love.

-cohabitation with ML
-friendship/ interests with SL
-ML /SL brothers
-brothers have old relationship issues with love for same person (father/girl)

Both dramas are historical and have a quirky tone. The MLs are of higher social status/wealth than the FLs, and the FLs earn their living in a way that requires they evade the law. Both FLs tell a lie to save themselves that connects them to the ML in some way (pregnancy vs. claiming to be possessed by his dead wife) and then end up telling more and more lies as time goes by.

both historical funny romances
male chases female first
ML tricks FL to marry him
ML seems like a bad guy but is actually righteous and cares for FL
both FL are smart and a little bubbly
both FL have photographic memory

Light tone, quirky FL and tone. Married couple in historical setting. At one point the FL lies to the ML about being pregnant to save her life, at which point his feelings toward her change.

The FLs in both have a false/someone else's identity and find themselves married to the ML. The FL dislikes the ML at first and the ML is initially cold and wants to get rid of her but slowly falls in love with her.

Both these dramas have similar themes of the FL marrying the ML with a false identity
They both also feel the same in the way it is produced and how it is delivered to the audience
Similar characters, family situation etc

Cold & fearsome first male lead. Silly girl disguises as something else to get into the ML's manor. The FL is initially fearful of the ML but gradually see the soft side of the fearsome man. The ML's cold heart is also slowly melted by the girl's innocence and truthfulness. They fall in love with each other. The ML has a younger brother (SML) who is also in love with the FL and helps her whenever she gets into trouble.

First male lead is powerful and feared by all. Female lead disguises as something else and sneaks into the man's mansion. After various mishaps, they fall in love with each other. The ML has a brother who is also in love with the female lead. He helps her whenever she gets into trouble.

Fake/forced marriage between the leads turns into love.
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