Responses
For BL I have:
https://www.mangago.me/read-manga/madk/
https://www.mangago.me/read-manga/murderer_llewellyn_s_enchanting_dinner_invitation/
https://www.mangago.me/read-manga/enthusiasm/
There’s a lot of smart and manipulative shoujo/josei manwhas if you wanted to look through that genre. Unfortunately I can’t remember a lot of shonen/seinen books that have this trope!
anything where the mc isn’t necessarily strong but cunning and can manipulate people to do stuff for him
something like the worlds best engineer