Princess Man is the sequel to Tree With Deep Roots (not the same producers, but the kings in Princess Man are the ones that follow the kings in Tree with Deep Roots historically). There are fictional elements in both dramas, but at least the names of the kings and the ministers are all real people. Tree With Deep Roots tells some parts (although some may be fictional) of King Sejong's accomplishments and on how he created Hangul, Korea's alphabet. It started with the reign of his father, King Taejong. Princess's Man, tells the story of King's Sejong's sons King Munjong and Grand Prince Suyang and what will eventually happen to their families. Han Myung Hee (a character that features in Princess's Man) also appears as a minor character and is mentioned by name in Tree with Deep Roots.

Both dramas feature Moon Chae Won in hanbok (where she looks extra pretty). Even though her role in Painter is only minor, it's still worth watching because it's her breakthrough role and her role in it is so unique. She has chemistry in her partners in both dramas that led her to win best couples with her respective partners. Both dramas are really great in general (in fact both were nominated for Baeksang). As of February 2, 2021, these are also the only two dramas that got MCW to be nominated at Baeksang Awards.

Both dramas are set in the Joseon dynasty. Villains in both dramas are kings (or will eventually become King in Princess's Man). Both main couples in both dramas are kind of "Romeo and Juliet" since the parents of the female lead is an enemy of the male lead (though there is less focus romance in Iljimae). Park Shi Hoo features in both dramas.

=> Same female lead acted by Moon Chae Won
=> Both male leads are acted by very handsome and charismatic actors
=> Both male leads are suspected criminals
=> Both male leads have a sister they love and protect
=> Moon Chae Won and her respective male leads have great chemistry in the dramas.
=> Both dramas answer the question: "Can love overcome all hate and evil?"

Tale of the Nine Tailed fans, if you are enjoying Lee Tae Ri as Imoogi, please let me inform you that it is not the first gumiho drama that he has acted in. 10 years ago, he acted in a drama called Gumiho Tale of the Fox's Child/Grudge the Revolt of Gumiho. He's only a supporting character here but his character is also quite important since he is the love interest of the gumiho child (played by Kim Yoo Jung). Notice also that he and Kim Yoo Jung also acted in Moon Embracing the Sun as child actors (although his love for her in Moon Sun is one sided).

Moon Embracing the Sun fans, please watch The Princess Man. Both dramas came out around the same time period (late 2011-early 2012). Both are also about romance and love stories between not just one but at least 2 couples.

I know the dramas are kinda random, but I just want more people to discover more of Moon Chae Won's works. The few similarities of both stories include a love story where the male leads have great chemistry with Moon Chae Won, a couple whose love must face a lot of difficult challenges, one of the main leads lies to the other about his/her real identity which causes problems later. In addition, both dramas also show Moon Chae Won's character being a strong female lead, at one point we can see her saving the male lead (Bonus: the male leads in both dramas actually acted together in 2008 kdrama Iljimae, so watch that if you want to see both guys act together). I find it also interesting that the male leads in the drama also have good friends who are both very persistent in loving their own respective love interests who are reluctant in accepting them at first
For Flower of Evil Fans -> you can see in Princess Man Moon Chae Won's top notch acting, Princess Man should be the first of her other dramas you watch since she won or is nominated for more awards for this show than any of her dramas as leads (including 2012's Innocent Man).
For Princess Man Fans -> as you've seen Moon Chae Won's great acting already, you can see in Flower of Evil her most recent work (2020). It's the drama that is worthy of her acting skills and her first and most acclaimed drama after 2013.
Trivia: Producer Yoo Sang Won is a producer involved in both dramas. He also did Lee Joon Gi's 2014 drama Gunman in Joseon

They have the same writers. They main character is also a twin in both dramas. There is a prophecy about the twin characters in the drama that is important to the plot. They also both have complex characters, meaning likeable villains, protagonists with a dark side, and characters which we won't understand at first if they're good or evil

Both based on the same novel, both entertained the possibility of historical Korean painter Shin Yun Bok as a woman pretending to be a man because her paintings mainly depict women. The two stories interpret the story of Shin Yun Bok being a real woman quite differently, but the similarity in both shows is that the historical character Kim Hong Do(who was a fellow painter of Shin Yun Bok in Joseon era) is her teacher and is also one of the 2 characters who fell in love with her. Both shows depict Shin Yun Bok's life as a woman loved by 2 very different people while living her life as a painter.

Both are Joseon period dramas about a woman's struggles to become a great artist. I really love both dramas because both plots explain the characters very well through the use of their art forms. Both dramas also feature a beautiful and talented gisaeng played by two great actresses (though the gisaeng in Painter of the Wind is NOT the lead female). A scene I find quite similar in both dramas is both feature a scene wherein the gisaeng is playing the gayageum instrument while her lover (in Painter of the Wind, this lover is the female lead) is painting as the lover listens to her music.

Both depicts a story of a woman who was born a noble yet circumstances in her life led her to be linked with a much older man (an official who owns her as a gisaeng in Hwang Jin Yi, a professional painter who became her trainer in Portrait of a Beauty). Both women are very talented, either as a poet or as a painter. Both older men are very much attracted to the young woman linked to them. Despite the older men's attraction, both young women fell in love with a man closer to their age who basically has a low position in Joseon's class based hierarchy. The love triangle in both these shows are then lead to chaos on the three main characters' lives until the ending.

Before actor Ryu Seung Ryong became popular with Miracle Cell No. 7 and Kingdom Netflix series. I have seen his great performances as a villain in these two shows that has a gisaeng as an important character.
(Bonus: As a result, while most people are surprised that the kind but imprisoned father in Miracle Cell 7 is the same guy in Kingdom, I am actually surprised that he could pull off a kind character in Miracle Cell 7 after seeing his villainy in these 2 shows).
These are the similarities of the 2 shows:
1. Both shows have a gisaeng as an important character (though the gisaeng in Painter of the Wind is not the main character)
2. Both gisaengs are beautiful and is the most desirable gisaeng in the land
3. The main villain in both shows is a much older official played very well by actor Ryu Seung Ryong, who lusts after the gisaeng. He was able to own the gisaeng as a property.
4. Because the gisaeng loves another "man", Ryu Seung Ryong's character wants to get rid of that "man".
5. The "man" the gisaeng loves in both shows are very talented in their own field (the one in Painter of the Wind is good at painting, the one is Hwang Jin Yi is good in martial arts)