In Detective Conan, I've Been Kidnapped by Human Traffickers a Billion Times

Detective Conan + Spy x Family + Bungo Stray Dogs + Armed Detective Agency + no saintly heroine + no CP + invincible + the Black Organization wins. If you can’t handle that, run. (Rei, Kaito, and Gin are invincible in this story.)

Jiang Fengying, a world-famous illusionist and magician whose true identity is an MSS agent, transmigrates into Detective Conan, a series she has watched over a hundred times, after an accident during a performance. She also becomes Kaito Kuroba’s older sister, Kuroba Kawakage. One accident after another leads Kawakage to form countless ties with both the Black Organization and the Red Faction. She also meets the Armed Detective Agency, whose members have transmigrated there by accident. So Kawakage establishes an Armed Detective Agency in the Detective Conan world. After that, she spends her uneventful days teasing Conan, Kaito, and Kunikida, stopping Dazai from going off the deep end, dancing on Gin’s last nerve, hitting the griddy in front of the BOSS, and casually (deliberately) revealing Conan’s identity.

Note: A lot of things will be unreasonable. Bungo Stray Dogs will moderately disrupt the Detective Conan storyline, and the two series will be written in alternating threads. Once again, a lot of things will be unreasonable. If you can’t accept that, run.