Potion-danomi de Ikinobimasu!

One day, the supervisor in charge of watching over Earth was taking care of a distortion, when they made a mistake that caused Kaoru Nagase to lose her physical body. Not only that, but reincarnating her into a different, less culturally-advanced world is the only thing they can offer to do for her. Not one to take this turn of events sitting down, Kaoru makes a demand: the power to create potions at any time she pleases, with whatever effect she wants it to have—and it doesn't stop there either. She asks for a magical Item Box, the ability to understand and speak every language, and the same body she had back when she was a fifteen-year-old girl. Using her newfound powers, Kaoru has to try and make a stable life for herself in a whole new world!

(Source: J-Novel Club)