dramaWanderer24

Both have MCs that rely on their strong sense of smell to pursue and solve cases. Both link to a past cold case of the MC

Both dramas have a hidden character who commits serial murders in the name of punishing evil for the people, revolving around the idea that law cannot give justice to all.
Both have two MLs and one FL leading the investigations, though in SH they're all official police, while just self-proclaimed detectives in TToS.
There is a little more bromance/brotherhood in SH comparatively, though both do not hold this focus.
In SH, its the ML who strongly pursues a cold case, while its the FL in TToS.

In both dramas, the ML and FL start off on the wrong foot, but gradually understand and care for each other through the drama. Both FLs also work towards empowering women to become female officials, althought it is not the main focus in Melody of Golden Age.

Both dramas have the trope where the female lead can look into others' memories, and makes a contract with the male lead to help him find past memories that were lost due to an accident/trauma.
The other aspects of the drama are different though, including the fact that one is in modern times and the other in ancient times.

Both dramas include the trope where one of the leads is "allergic" or gets nauseous when touched by the other gender. In Walk Into Your Memory, it's the male lead, whereas it's the female in You Complete Me.
Apart from this though, the other aspects of the two dramas are different.

Both dramas involve the ML being asked to pose as his twin brother. In Fervent Kiss, its by his uncle, and the FL takes time to figure it out, whereas in Be Your Knight, the FL drags the ML into the story and the rest of their family, mainly their aunt, figures it out over time.
The rest of the dramas have different vibes, one in modern setting, the other in a more dangerous republican era setting.