Alex

Cold and closed off guys who prefer to work alone are assigned a new cheery and excited partner.
They prefer to stay in the "basement" while their new employee does most of the work outside.

Female lead goes "undercover" into a family business, with the intent to seek revenge for a crime from the past that her family member was severely affected by.
Romance occurs between female lead and male lead (the son of the business).

Female lead goes "undercover" into the home she once lived in as a child, with the intent to seek revenge for a crime her mother was framed for.
Romance occurs between female lead and male lead (the son of the household).

Male leads disappear from female leads' life after briefly dating in high school.
Later, female leads have begun dating an old friend, when male leads suddenly reappear in their lives.
They soon learn the secret reasons behind their disappearances- WS ML has memory loss, S ML has hearing loss.

Romance plot set in dessert/bakery shoppes.
Leads start with a bickering dynamic.
Male lead falls for female lead first.
Additional love interests in the form of supporting characters.

Gender swapped in a way. Character's father was murdered by a thought to be friend, who then marries his widow. Child grows up in a family that mistreats them due to being unrelated.
Main characters briefly meet while children, then reunite in adulthood.

Gangster world/setting.
The subplot of Dae Su & Jung Ae in AI reminded me of Gil Ho & Jae Hui in GBS.

Both legal dramas.
Both feature a mentor/mentee dynamic between female lead and an older (middle aged) female boss.
The middle aged woman goes through a divorce and has a child with ex.
Female centric, slight romance.

Criminal father with an evil son and sweet but naive daughter fall victim to a revenge plot from the son of a single father.
This son seduces the young daughter of the family as part of his plan.
Hit and runs also important plot points from both.

Genius and eccentric university students assist police with cases.
Female leads have a crush on the male leads.

Female lead becomes a cop/detective after the murder of her sister to seek justice.
Forms a new sister like bond with second female lead.
Older male cop/detective helps female lead become one herself and serves as a bit of a mentor.
[ SPOILER ] Male lead female lead grows close to while working later dies.

Romance genre with hard hitting/insightful life circumstances.
Female lead is raped.
Male lead doesn't know it happened for the first few episodes, later finds out. Helps her overcome it.