While not dealing with the same issues at all, they both have very strong FL and ML who cares more for her than the material world.
They are both funny and have real, modern day romance!

Both historical with modern vibes and good comedy moments.
Love triangle between a king, nobleman and a girl commoner
FL is pretending to be someone else.
FL was supposed to marry one of the MLs but fall in love with the other.
Very strong SML syndrome in both dramas.
High officials plot against the king.
Both are lighthearted and worth watching.

** This is written before I finish watching TFM
Similarities:
- Both are set in historical time but completely fictional (modern day behaviour)
- Have strong comedy borderline parody
- Somehow heavy on political conspiracy
- FL is kind of reckless sometimes rude in both dramas
- ML is nice and understanding
- Love triangle doesn’t work in both

Differences:
- Revers character hierarchy
- TFM is giving strong SML syndrome
- TFM have better romantic chemistry and swoon moments.