Slav Squad/ Slav Wars( still thinking how to name it):
Assassin dies and is reincarnated as a wastrel miss of a noble family, she meets overpowered guy who wants to stick his dick in her.
But she already had a husband, who is looking for her. He strikes the deal with a "Devil" and is reincarnated in that world too, and his friends too. Who will win Slavic Warmongers or that guy and his forces? Her husband is nicknamed Kilgore.
Stolen from Royal Road, this story should be reported if encountered on Amazon.
Title unknown:
Gender bender story, modern weapons, reincarnated as a demon queen, or more like the goddess of chaos. Under the name of Slaneesh. WH 40k, sword and magic, hero.