18 Again

Both of shows include one of parents who reenter the high school/college life after many years being married and raising their childs.

The main common points the couples are about to be divorced and parents (female in 20 again and male in 18 again) are in the same college/school of their childs.

Female leads are trying their luck to study the major she wanted in 20 again and the job she dreamed before marriage in 18 again.

Both of female leads having same character of innocence and being criticized by their surroundings for being older than their colleagues.

Shows of second chance in life and love theme but fantasy genre in 18 again where the male lead return to his old young self to rectify all his mistakes.

slice of life, family, romance, friendship, youth, school, love triangle, hardworking male lead, strong female lead.

Similar in the way that an older male gets to somewhat relive youth.
They're very different concepts though, because The Dude In Me involves body swap.

They both have a feel good - light hearted type drama but have elements that make us think and cry with the characters. The characters have flaws and try to become better version of themselves. These dramas are about giving second chances and about how being expressive matters. Talking about what you actually feel should not be something to be embarassed of. They both gives us lessons and reality checks.

Father and son same age in high school on both dramas
There is friendship element in both dramas
Both fantasy dramas
Both youth dramas

Similar that both dramas are about being your younger self again...The only difference is, in 18 again, its a man; in Sumika Sumire, its a woman.

If you liked the character developments, the unexpected surprises, the life lessons, the realistic set with fantasy (I know it's contradictory lol), the cute and fluffy youth romance, and the going back in time type of coming-of-age dramas, I Don't Want To Be Friends With you is perfect for you! You also might need a box of tissue :')

both of them have body change element, married couple, husband has the same age as their son, age difference

both leads end up going to their past selves. in 18 again, the male lead is transported to his past body and lives in the present day. In Reset Life, the female lead is transported to the past and lives in the past life.

Both are great dramas about second chances and having a second shot at life

The two dramas are faced with being the same age as his parents because of time travel. The two approach the family in all its aspects. And the lead meets love in his journey.