Recommendations

Same plot...girl time travels to past. An amazing drama with amazing cast

the main couple in both dramas are really cute and have great chemistry :)

It's the second movie of this one, so it's bound to be similar.

They are both supernatural. In Gumiho, the main girl is not a human and in order to become one she needs a human. She is +500 YO.
In Goblin, Kim Shin is not human too. He is +900 YO. He wants to end his immortality. In order to that he needs a human bride.
Goblin has more interesting storyline and has a strong sweet bromance too.

Both of these dramas are about high school students have have a cutesy feel as well as supportive friends. Both have shared actors - Sakurada Dori and Shiraishi Shunya!

both have a similar feel to it. Jenius focuses more on investigation and sci-fi while Simple Man crosses many genre from sci-fi to investigation, action, mystery, medical and paranormal. Personally, I prefer Simple Man over Jenius but both are really good dramas if you are into cleverly made quality mystery, investigation type dramas.

Plots of both stories are really similar. Both are about unfortunate love in Joeson era that repeats again in our time to have happy ending. There is a little of fantasy also: mysterious time travelling in Rooftop Prince, and mermaids in Legend of the Blue Sea. Main characters have troubles adapting to modern world. And after all both series have charming love story.

Teachers with secret identities.
Yankee students.
Life lessons.

Both contain female doppelgangers belonging to opposite ends of the social pyramid, where the poor one must take the place of the rich one in a relationship with the rich lead without letting anyone know

Both involve corrupt politicians, crazy royals, and concubines. The Treacherous is a lot more gritty, but both explore themes of revenge, lust, greed, desire, and power.

Revenge plot galore, great productions, great acting (personally like Nirvana in Fire a bit more because it felt more cohesive and Hu Ge was an amazing actor... however, same can be said for luo jin in The Princess Wei Young)
The romance in nirvana in fire is more toned down than in WeiYoung. Both are highly recommended if you like smart heroes/heroines, political drama, and revenge

If you want to fill the void that Scarlet Heart Ryeo left, this drama is a great reliever. Like Scarlet Heart, it is a historical drama wherein several princes are fighting for the throne and surprisingly *insert the sarcasm* they are also vying for the love of the heroine. But what makes it better is that it is well - written. It has 54 episodes, which I hope you have the patience to finish, so it isn't that rush, unlike you-know-who. The heroine in the story is so much better. We’re at the point in the story where our heroine is being stomped on and typically, she’d lose heart or stay cheery and upbeat in spite of her circumstances. But not Wei Young. She’s more of the, “You might have the upper hand now but I’m still not taking your shit.” type heroine. All in all, JUST WATCH IT :)

Both star Jung Woo Sung as the main lead suffering from memory-loss.

Both take place in convenience stores with weird characters and strange occurrences happening regularly.

contract marriage relationship that brought the couples fall in love.