She's a Herrscher and she's pretty sure she's in the wrong series. Instead of being reborn in that anime world featuring an all-female caste of supersoldiers and a worldwide militant church, she's in a superhero deathworld where people get powers from trauma and is now in an enviable position of facing down two multiversal-scale apocalypses.
Or:
Depressed magical girl punches super nazis and space whales.
A Worm crossover with Honkai Impact 3rd. Because the plot bunny birthed a new one...
Becoming a pile of nanites in a vaguely human shape was not what one would expect after dying. Becoming a pile of nanites in a vaguely human shape that also has a universe-jumping drive and millions of years of technology to play with? At least that took the sting out of it.