Food!

That's really all I can say. There's a lot of food. The mains in both are chefs. The stories both have love triangles.

Very similar when it comes to moments between the leads.
Xu Kai's character in both has a lot of action scenes.
SEL is more geared to a younger audience. It's more campy.
WoL is more adult and political.
Both FLs are powerful and fight with the ML
Also have to give props to the costume department in both because ABSOLUTELY STUNNING!

Both about esports and being a professional esports player.
FIYS has romance as it's primary plot though
TKA's game moments like the actors are the players in the game, like they are being sucked into the game and actually fighting, meanwhile FIYS is more obvious that they are playing a game but I think the animation in FIYS is best and it has better fight scenes in my opinion.
Both leads are incredibly attractive

Xu Kai plays the same character personality-wise. Very cheeky, intelligent, and charismatic.
He also finds out the cross dressing girl is a girl before anyone else.

Both deal with bullying.
Both gritty.
Both have bromance.
Both are amazing dramas that I think the actors played phenomenally well in. Everyone is an MVP. Actions scenes are amazingly choreographed and realistic.

Both have Lomon.
Both in high school.
Both have gritty vibe.
Both have great fight scenes.
All of us are dead is a thriller while Revenge of Others is a murder mystery.

Same vibe of playful and happy love.

Have a semi serious background plot, but the majority of the show revolves around the leads love/getting together.

Strong woman has a love triangle.

Both have cute pairings who love to tease each other.
Both revolve around the workplace.
Both have leads with past connections to each other.

Both deal with animation.
Both romances.
Both have love triangles.
Both fun and lighthearted.

Extraordinary You has more storylines and characters. It's more fantasy based and magic based, while Yumi Cells (2) is about inner feelings and thoughts. But they both have the same Webtoon feel (probably because they were both Webtoons/ have Webtoons in their plots).

-Both based on Webtoons
-Watch Extraordinary you first and when you watch True Beauty a couple familiar faces will cameo which is a real treat
-Love Triangle
-Be ready for a lot of clichés that the shows are super aware of.

Both with a really cute couple. Love triangle that can make you have second lead syndrome. Light hearted comedy.