I’ve recently seen  : “King is not easy”, “ My secret Garden” and “Go Princess go” and had enjoyed all 3. Can anyone recommend me more gender swap dramas? I love especially how the MLhad to cope with having their periods in all 3. Their reactions had been hilarious! In “Go Princess go”, he had really over-reacted, lol, had found it extremely entertaining. More scenes where ML has to deal with having their periods for the first time? 

All the gender swaps that I've seen other than what you have watched already, whether I liked it or not :)

Dramas:

  1. Ohlala Couple 
  2. Proud of Love 

Movies:

  1. Daddy You, Daughter Me 
  2. If I Were You 

Oh My General

This isn't necessary a gender swap in which the male and female swap bodies but more a gender role switch in which the female lead is a bad ass general ( think Mulan) and the male lead is more feminine lol. Just total crack. Even his concubines falls for the general and conspire to keep them together. 

https://mydramalist.com/33917-the-rules-of-love 

It's not a good drama at all and I'm still not done with it, hence I can't tell you more about plot but it has a theme of gender swap.