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two develop a loving relationship in spite of the emptiness she feels after losing her family.

they try to figure out how to live their lives

father-daughter

Same writer. Even though Black Out is based on a book, you can see similarities in the writing styles through the adaptation. Black Out also has a similar setting for the main character where he is seen as an outcast and is despised by the rest of his village community. Lots of injustice like Save Me 2 to the point it will infuriate you even more with how despicable most of these characters are in their actions.

The main character partner dies and their heart is transplanted into someone else and they happen to meet this person. But in Someone Like You the main character has to decide between a woman who looks just like his love and a woman who has his love heart.

This is a Chinese remake/adaptation of 'Splash Splash Love', available on Viki (the other adapation isn't).
It follows the original closely in several ways - heroine goes back in time due to rain, where kingdom is experiencing a bad drought, she arrives in exactly the same way, is mistaken in the same sort of way, becomes a 'eunuch' who serves the king/emperor, and helps him through her modern school-girl knowledge, there's the taciturn and loyal guard, and so on.
It gives its own spin to several things as well, with the heroine's character being similar but also uniquely this actress's (she's great, especially as the 'eunuch'), the hero being similar but also unique, with his own character/personality, individual characters you come to like, a band that forms that you feel/want to be a part of, doing good in the kingdom, it's a fictional place, not a real past, there are different side stories and villains, etc.
It works these similarities and differences in well, retaining some of the best parts of the original and making it its own at the same time, in a way that keeps it interesting. Still very Chinese (lots of makeup, repetition, extreme cheesiness in places...), but a decent one at that.

If you loved Sun Jae's loveable dorky awesomeness, you might also love Ji Hwan's loveable dorky awesomeness! This similarity in vibe was an early factor that endeared 'My Sweet Mobster' to me. Quite different characters, but it has that link. The perfect heroic combination that makes us love a character so easily.

They also both have some very funny, silly or crazy humour.

What makes these similarities work is that they're not similar shows; they just have these somewhat intangible elements in common. No repetition of themes or a re-interpretation, no time-travel similarity or anything like that. Just something about the heroes that is wonderfully similar.

Both follow an office-working female lead meeting and later convincing an everyday street-smart type of guy to have a fake relationship with her.

Both have an older style and the male leads intentionally approach the fml for a purpose sorta have the same feeling

Idk if this was mentioned on not but I've been looking for things like this and finally found something close enough both have revenge which also involves getting closer to the girl to get their revenge

Both dramas are movies about zombis. In both they are the accidental production of a group of scientists. In both people try to find a way to survive. While there is a greater plot with The Cursed than with Train to Busan, both give off the same feeling.

Both are korean dramas are about zombi. In both dramas they are associated with, a curse and in both dramas people try to use them for their gain.

Both are about zombis dramas. In both a facility that wanted to create something different but accidentally ended up creating zombis instead.
Both have a male-female duo trying to investigate the situation and find solution out of it.

both have the concept of getting rid of ghosts for "work"
in both they have to learn the will of the ghost in order to exorcise them
they feel very similar

The two dramas were based on a novel named “The Nineteenth Floor of Hell” by Cai Jun.

19th Floor is more aesthetically in line with today’s viewers in terms of plot and cinematography. It has more romantic development and a dramatic difference in film quality. 19th Floor is about a group of people from the same school who were forcibly transported into a VR game. They then had to survive in the VR game without a clue as to why. Their goal is to find out why they were in the game and find who the mastermind is.

Naraka 19 was made on 2007 and has a more silent/music over silence than 19th floor which has the environment sounds. It is a bit confusing however there’s a bit of a thriller vibe. Gao Yuen (aka Jeremy Tsui) is also so goodlooking in this movie. They speak in cantonese and it definitely isn’t very well-done in terms of plot. However if you want to watch an old movie, you can watch this. Its a movie about a girl named Rain who was suddenly sent a message from her friend to meet at the old haunted school building to take a picture. Mysterious things began to occur and to solve the mystery of her friend’s weirdness, she follows the instructions sent via SMS and entered the game: 19th Gate of hell.

Both movies deal around a natural catastrophe that set the world into chaos. In both dramas the characters have to find a way to survive. The only difference is that Ashfall revolves around a volcanic eruption while The Calm Beyond focuses on tsunami due to a storm.

Watching one reminded me of the other. Both take place in a dystopian world where each has to survive. While The Calm beyond focuses on a natural catastrophe and the aftermath of it, Alice in Borderland pulls the people into a game.