Mizu Mahou gurai shika Torie ga Nai kedo Gendai Chishiki ga Areba Juubun dayone? Though I've Got Nothing but Aquamancy, It's Enough to Have Modern Wisdom, Isn't It?

Synopsis

Frim, a 5-year-old orphan living in the streets of the slums district, was a Japanese person in her past life. Her everyday life is filled with violence and injustice, and she has no one she can rely on for help. All she has is "magic that can produce water" and "modern knowledge." Even hoping for a roof to sleep under is a luxury under such circumstances. But this world is lacking in things like ideas for improving working conditions, and by coming up with new ways to use aquamancy aside from producing potable water, Frim gradually makes her presence known! (Source: Kadokawa, translated)