Echoes of Vengeance: The Sweet Wife's Perfect Revenge - Chapter 12: The Devil at the Door

(following the boat) When a person who can get random superpowers every day enters the world of pirates and joins the protagonist group, what will happen as a result?

Luffy: “Si Guoyi! Lin Bei, let’s jump from the sky again!” Kebi: “Please don’t!” Sauron: “Be sure to leave Lin Bei’s room at twelve o’clock every day!”

Nami: “This bastard, just let me…” Akainu Sakasaki: “Bastard Lin Bei, turn me back into a man!

The old lady used her ability to come to her aunt once! “Big” boys, come and meet your father! “Lin Bei:!!! This really doesn’t exist!!!

- Description from novelbuddy

He became a teacher at the best magic academy in the empire.
….For being mistaken for someone else.

Xu Mo, a modern high school student was sent back in time to Jing Kingdom and found herself trapped inside of the body of a princess with the same name.

She had barely recovered when she learned of an unparalleled fiancé and in a daze, they got married. Then the stunning genius physician who normally does not pay attention clamoured to marry her. After that, there was a cold general, a flirtatious lord, a tsundere young master……

As it turns out, this was a male-dominated dynasty. Because the female population was sparse, the entire nation shared wives regardless of rank or nobility. Is it feasible for someone who wants to maintain monogamy in this dynasty?

- Description from Novelupdates