Ghost Possession or multiple personality dramas?

Your list basically listed all the multiple personality/ghost possession ones. 
But since u included gu family book I guess mythical power possession also works. I have a few dramas but they're chinese.


- Sword of legends (the main guy is 'cursed' with a mysterious aura/power within him, his personality changes when the aura gets released)
- Classic of mountains and seas (halfway through the drama, the main guy has a major personality change)
- The four (the main guy is part of a wolf clan so his personality changes sometimes)

- master's sun (this drama is about ghosts, there's one scene of possession i think)

Master's Sun

Oh My Ghostess, Master's Sun and Kill Me, Heal Me come to mind, the first two being about ghosts and the latter about multiple personality disorder.

There's a drama starting this Juli called Bring It On, Ghost with a description that also fits the bill.

EDIT: whoops, didn't see your already watched list!

The Master's Sun 

Falling for Innocence - guy gets a new heart 
I Love Lee Tae Ri - boy becomes an adult
Sort of:
Mask - girl takes over the life of someone who looks like her
Bride of the Century - same as above.

Soul - a short 10 ep drama with Lee Seo Jin from 2009 has ghost possession
Go Princess Go - kind of similar to Secret Garden (guy wakes up in a girl's body in the past. low budget drama but I think it's really good considering that)