Moon Lovers: Scarlet Heart Ryeo (2016)

It's the korean remake of Scarlet Heart originally written by Tong Hua, anyone wants to know what might the thai adaptation look like can try this one or if anyone liked the thai version should try this

Story wise they're not very similar, but they are both historical dramas.
Battle of Changsha shows more historical elements, while Scarlet heart is more emotional.
They're both dramas that will take you on a ride of emotions.
Although in scarlet heart there is no War; it shows the mistreatment the fourth prince faced and how he climbed his way to the throne

Synopsis of Scarlet Heart:
When a total eclipse of the sun takes place, Go Ha Jin is transported back in time to the start of the Goryeo Dynasty of Korea during King Taejo's rule. She wakes up in the body of the 16-year-old Hae Soo and finds herself living in the house of the 8th Prince Wang Wook, who is married to Hae Soo's cousin. She soon befriends several of the princes and meets the ostracized 4th Prince, Wang So. Although knowing she should not get involved in palace intrigues over the succession to the throne, she inadvertently becomes a pawn in the struggle, as several of the Princes fall in love with her.

Scarlet heart and Bloody heart is both historical drama that is also a romance drama. Both main lead becomes the king.

The main actress is also in Scarlet heart too!

A popular teenager inexplicably finds herself in the body of an unpopular classmate - and her body's new owner has no intention of switching back.

The series centers on Ayumi Kohinata, a first-year high school student who has a cute and shy personality. She's excited that she just started dating her first boyfriend, but on the day of their first date, she gets a mysterious call from her classmate Zenko Umine. Zenko says she's going to die, and Ayumi witnesses Zenko jumping from a building. The next thing she knows, Ayumi wakes up in a hospital, but in Zenko's body.

Both are about a modern day FL who travels into the past and finds herself in a love triangle involving at least one prince.

After an accident, the soul of a 21 century woman traveling back into another time/paralele universe into the body of a dying woman. But is the Korean version of the c-drama "Scarlet Heart". Like "Palace" (Gong) It is a melodrama.

Both are about a person time traveling to a very different era - one is past to future, the other future to past.

There is similarity betweeen princes in ML and three friends in GF, characters was changing from harmonious friends to enemies in both shows.

Not too similar except the fact that Lee Joon Gi is the lead in both dramas and the romance of his character and the female lead are crucial in both dramas.
However, I am recommending Flower of Evil to Moon Lovers fans because Flower of Evil is such an underrated drama and more people need to watch it. I know Lee Joon Gi has many fans from Moon Lovers, so I hope his Moon Lovers fans can watch Flower of Evil. Don't undersestimate the female lead, Moon Chae Won may not be the most popular to today's kdrama audiences but she is an acclaimed actress and she has great chemistry with Lee Joon Gi.
As for Flower of Evil fans, it is good to recommend Moon Lovers since it is indeed one of Lee Joon Gi's most popular roles, it's a good idea to watch it for Flower of Evil fans to understand why Moon Lovers fans hype Lee Joon Gi's role in this show so much. And Lee Joon Gi did a great job in this role too.

Both are about a modern day FL who travels into the past and finds herself in involved with at least one prince.

Both female lead were favor, but has sad ending.
Both female lead were kind, beautiful
Both young ming were down jealous, no confidence, palace politic

Both are about a modern day FL who travels into the past and finds herself unexpectently falling in love.

The beautiful female lead and the young king were deeply in love.
Due to stupid young king and palace conspiracy, dirty politician, they were apart
Can’t get my eyes off the queen
Beautiful historical drama

Both are about a modern day FL who travels into the past into the body and identity of another girl.

Both were historical drama.
Both female leads were beautiful.
The main lead were deeply in love
However, ending were sad