Recommendations

1. Both of their main characters have unusual abilities.
2. Both HIAP& WYWS's antagonist appears to be good at first.
3. Both are love stories.
4. both have crime scenes.

Both main lead actors (male and female) are smart and cheeky with similar personality, the way their romance developes is also similar as they try to trick one another but end up falling. Both have a lot of rom-com in it with good intense chemistry. Just the main difference is that the eternal love takes place in palace while in hua rong its more about adventure filled with free lifestyle and side missions.

Both main characters secretly perform many tasks even under the eye of the king. They also both have secret identities.

Both drama set in large-scale catastrophe, showing how the characters face ethical dilemmas in life-or-death situation.

- Both are crack-addictive makjang dramas with over-the-top/persistent villains and family mysteries/pasts
- The female leads are naive and trusting of villains at first but they both become stronger characters later
- Both male leads have a transformation in looks (one would be from weight loss but the other is plastic surgery) and are given a new identity
- There is little romance in both but the scenes are satisfying to watch
- Both male villains (Lee Hyuk, Kim Nam Joon) are obsessed with the female leads
- Some characters and situations are somewhat similar in a way (but may be spoilers listing them)
- Both dramas have kind-hearted grandmas

The male lead also got amnesia after getting plastic surgery and changed his identity, both of them took a while to remember their original self
Kim Sung Ho and Son Joong Ki characters are a bit similar

Both dramas feature female leads dealing with crippling insecurity that they learn to slowly overcome throughout the story alongside male leads who are thoughtful and kind and do their best to lift up the female leads and help them see how worthwhile they are. Both dramas also tackle sensitive and important topics such as plastic surgery and agoraphobia and self esteem and the fear of judgement and/or hatred from others.

Modern Man travels to the past and uses his modern knowledge to improve the lives of the kingdom... It's basically the same story but Tang Dynasty Tour has more drama and Man Comes to Tang Dynasty is more comedy

In both serial killers have destroyed the protahonists life and the couple investigate together the crimes.

The investigation is the centre of both of the shows and there are some surprises that nobody saw coming in neither of them.

You have single mother's fighting for their future in both.

In both male leads fall in love at first sight and both are really optimistic and hardworking.

Both dramas have this great feeling and healthy relationships in their couples.

In both there is a serial killer that is involved with the female lead.

Both male leads are gentle policemen that face their problems at the same time they fall in love.

In both there are amazing support roles that make the story more lively and funny.

Family bonds and mothers with mental deseases are present in both too.

Both deal with single parent homes and difficulties that they face when it comes to relationships.

The soundtrack of both have a unique vibe that transmits a lot through the scenes.

They both have sweet but strong male leads that make you change your idea of the perfect man.

Both dramas are connected with work issues and the career of the main characters.

The couples have a strange connection that trascend ultimately the work environment.

They both have the same vive and fresh feeling with many charming support roles and funny scenes.

The characters have the same age, and they face problems related with their jobs and carreers.
The couple know eachother for a long time and its after some events they get to love eachother.
Some characters are really dense and funny at the same time wich lead tho many hilarious secenes.

Both dramas have similar fresh feeling and a great balance between love and work issues.

The whole plot is kind of similar tbh...
Especially the moment when the lead “couples” communicate.