Recommendations

Rush to the dead summer is about a girl who's in love with her class mate but her friend likes him to except she got rejected later on they all go to college than the main girls friend tries again but.....

Both have the same Robin Hood-esque, team of thieves vibe. Great music, story, and expressive actors.

'Stray Kids' first reality show which stars the winners of the 'Stray Kids' survival show created by JYP ENTERTAINMENT. Kim Woo-jin, Bang Chan, Lee Min-ho, Seo Chang-bin, Hwang Hyun-jin, Han Ji-sung, Lee Felix, Kim Seung-min and Yang Jeong-in to star in this new reality show.

Hwayugi gives off some very strong Goblin vibes. In both series the female protagonist can see spirits and is surrounded by ghosts and other supernatural creatures. Hwayugi however has a lot more deities involved. I've seen a lot of people say Hwayugi was something like the lovechild of Goblin and the anime Inuyasha. If you liked one, you'll probably like the other!

In both dramas...
-Female and male leads are in an older women younger man relationship with both guys being in high school
-Second male lead also has issue with his father
-Male lead and second lead's father have issues

A movie of a vampire who falls in love with a boy when she was little. This movie has a feeling of vampire views and shows the life of them

This is the Chinese version of operation proposal. The only thing that is common is time traveling. Heart melting romance in both dramas are same

As our main plot is time traveling, both dramas are about this. It's different in many things. This is about a man who time travel to propose his first love and to stop her from getting married.

Same director Jeffrey Lau. Charismatic comedy and romantic at the same time in a Chinese folk story context. Cheese CGI but who cares! Beautiful natural landscapes and atmospheres. Good combination of chinese folk tunes with modern stuff.

Actor Stephen Chow now directs. Good casting, funny jokes and nice music and art direction in regards of character make up, costumes, and special effects.

Similar story but more with an erotic background, and how lust can drive you to unpleaseant places. It has a lot of humour and erotism, mixed with ghosts and demons, so it does not get very preachy about morality and lust.

Tragedy romance about love between two different spiritual realms, moral story, beautiful music and landscape atmosphere.

They remind a bit about each other plot wise and with the female leads. Both female lead have "good hearing".

Considering how similar the main couples are in these two dramas. I'm surprised it's not even recommended. The genre is completely different. Memory Lost is a detective drama. The elite detective team vs. a team of criminal masterminds.

But I think Memory Lost amends the main weakness of Love O2O. The lack of chemistry. Xiao Nai is more often creepy than charismatic. Bei Wei Wei rarely shows any emotion other than blushing. While handling of plot, side characters etc. is awesome. A romance drama is incomplete if you can't feel the chemistry between the leads.

On the other hand while Han Chen is pretty possessive like Xiao Nai it comes off as more lovey dovey rather than creepy. Acting of Bai Xin Ji is leagues better than acting of Bei Wei Wei. And you can feel the chemistry between leads almost immediately.

Comparing the two in Memory Lost you get a way better OTP and a more exiting plot, with good twists, in Love O2O you get excellent side characters and realistic geek environment (Unlike some infamous shows).

Both involve a female protagonist travelling back in time. They also become involved with important historical figures of that time and contribute in politics/strategies using their knowledge from the future.
Splash Splash LOVE is definitely a lot shorter, but it's worth a watch if you want something quick and succinct.