I know a few with strong female leads but "inventing things" might be a bit too hard to find ( ̄∇ ̄")
https://www.mangago.me/read-manga/doctor_elise/
https://www.mangago.me/read-manga/a_stepmother_s_m_rchen/
https://www.mangago.me/read-manga/the_way_that_knight_lives_as_a_lady/
https://www.mangago.me/read-manga/the_villainess_reverses_the_hourglass/
https://www.mangago.me/read-manga/may_i_ask_for_one_final_thing/

can you recommend manhwa like this where fl o ml is smart ang invents a lot of things thanksss