Recommendations

They are both gender benders with a girl dressing as a guy, both guys fall in love with the girl and think a they are gay and try to resist. Both guys even end up going to visit a psychiatrist doctor to cure them of their gayness

scarlet heart 2 is the second season of scarlet heart !!!!
so you need to watch scarlet heart and then scarlet heart 2 !!!

Very similar themes - an abusive and dysfunctional relationship and problems with family relationships

Banjong Pisanthanakun and Parkpoom Wongpoom directed both films. Both films also have a twist ending.

The director of Alone also directed the fifth story in Phobia 2. Both star the same lead actress and the fake movie in Phobia 2 is a sequel to Alone.

They are both extremely WTF, hilarious if you can handle the wtf, but horrible if you can't.

Li Chi Ling has a main role and acts well her part. It's a romance worth watching.

Both psychological dramas, both deal with manipulating other people into looking into themselves and may be changing for the better. Both have a cute and crazy lead character with a past. :)

Both main leads led cold life's and became close to awesome female leads with an ability to see dead people.

Raak boon female lead is very strong willed, feisty and doesn't want anyone's pity.

It's the predecessor to Reply 1994 - it aired first and is, obviously, set in the future but some of the characters from 1994 interconnect with 1997's at a point. It also has the same general feel as 1994.

If you enjoyed the main story arc on Joong Won past in Master's Sun you'll enjoy Bride of the Century, it almost feels like a spin off.

In both story line the heroine has to pretend to be married to a weathy man because of a lie.

If you haven't seen the other seasons then I recommend that you should watch it.

Lee Seung Gi is the male lead in both dramas. Both dramas have the same gumiho theme.

The female in Phoenix does outrageous things, another good romance/ revenge story.