Both involve cross dressing women who are good fighters. They both involve a strong political story with cunning women. They both involve women who are secretly from very powerful backgrounds with the potential to change their countries drastically. They both have love triangles, though Queen Seon Deok focuses less on it.
Though both sageuks have different target audiences in mind (they have differences as if you want some smart political talk you should watch Queen Seon Deok rather than Moon Lovers) they have sone similarities:
> lots of male fanservice (hwarangs in Queen Seon Deok, princes in Moon Lovers)
> the female leads love one man first then she turns to love a man with a darker past (plus both men wear black most of the time, I'm talking about Bidam and Wang So, Kim Nam Gil and Lee Joon Gi Yeah!)
>both the second men the female leads love have mothers that are obsesses with power plus those mothers abandoned those sons too
> both evil mothers have other sons they prefer over the son (the men loved by the female leads) they abandoned without realizing that their abandones sons are the smartest and their closest ticket to power
> lots of male fanservice (hwarangs in Queen Seon Deok, princes in Moon Lovers)
> the female leads love one man first then she turns to love a man with a darker past (plus both men wear black most of the time, I'm talking about Bidam and Wang So, Kim Nam Gil and Lee Joon Gi Yeah!)
>both the second men the female leads love have mothers that are obsesses with power plus those mothers abandoned those sons too
> both evil mothers have other sons they prefer over the son (the men loved by the female leads) they abandoned without realizing that their abandones sons are the smartest and their closest ticket to power
