Recommendations

Both Dinosaur theme Super Sentai
Both have a "evil 6th ranger"
Both were in a crossover with Kyoryuger
Both feature a Red Tyrannosaurus Rex and Blue Triceratops

Both are Magic themed series
Both owned by Toei
Both fight mythical monsters and beings
A "red fire" wizard protagonist

Both were adapted into Mighty Morphin Power Rangers
Both were written by Noboru Sugimura
Both fight ancient supernatural forces
Female ranger is bird themed
A Ranger have a Father who went to the dark side

At first, they may seem different: Love O2O, being focused on gaming and college life while It's Okay, That's Love, being more focused on psychology or healing.

However, after watching both of these great dramas, I'd say they somehow share a similar vibe, which may be because they both have:
-natural yet off the charts chemistry between the leads
-strong and mature relationship, where both sides support, respect, and trust the other person through thick or thin
-skinship and kissing scenes (or fluffy moments, in general) enough to make you root for the main couple (although IOTL is a lot better and intense on this one)
-admirable character and/or couple development (the lead/s definitely exhibit growth throughout the episodes which further helped strengthen their relationship)
-happy and satisfying ending

*there are probably more similarities, but these are all I could think of right now.

The two female leads time travel into the past, they have fun.
The male leadsls deeply fall for the girls.

These dramas are similar, because they both include: vengeance, violence and romance. Main male lead is agreesive and cruel (because of the past, misunderstanding) towards to a female lead.

Both based in the fashion world and include both work related and romantic challenges throughout. Both female also leads seek for perfection.

Both are Ninja series owned by Toei
Both fight demons/supernatural
Both have a American Ninja
Both appeared in Ninninger
Heroes inherited power from relative or descendant

Both are Ninja themed
Both have a female white ranger, a male red, blue and yellow ranger
Both fight against demons
Both are Super Sentai series
Both met in a crossover

Both are Ninja theme seasons with hints of both dark and comedy elements
Both have only a sole female member
Both are from the Super Sentai franchise owned by toei
Both had made a crossover to Ninninger

This drama is similar because of the Time Travel, romance, comedy, and Historical time period. Both also involve politics.

Has a similar story base: a male lead who has super natural powers, a female lead who isn't really super successful, and the interactions they have as they are roommates.

Ghosts, reincarnations, mysteries, karma, do I really need to say more ?
Thai make good ghost stories

Another Korean TV Idol show where Taemin is acting judge, taking on a more critical role on the panel.

Dance show featuring Taemin.
In this show he' competes in choreography, together with his dance partner/choreographer of SHINEE Taemin; Koharu Sugawara.