Responses
Lol this is the most recent one that i read which matches... https://www.mangago.me/read-manga/an_incompetent_woman_wants_to_be_a_villainess_the_daughter_who_married_as_a_substitute_for_her_stepsister_didn_t_notice_the_duke_s_doting/
Stories in which mc goes into marrying Ml in place of their sister or brother, who then end up regretting and embarrass themselves trying to get Ml ?
I've read many stories with that plot but I can't seem to remember the names today except for :
https://www.mangago.me/read-manga/the_evil_lady_will_change/
https://www.mangago.me/read-manga/usotsuki_na_tsugai/
https://www.mangago.me/read-manga/shadow_queen/
Anything else (genre doesn't matter) ?