Pest ga Aketara Asobimashou! ~Chuusei Europa Sekai to Gendai Bunmei Slow Life~

In 14th Century Middle Age Europe, the spread of the Black Plague has led baker Rachel Becker to move from the city to a village. There, she meets Ema Muller, a "witch" who claims to come from "another world" 700 years into the future, bringing with her modern technology that feels like "magic" to the people of the middle ages...

(Source: Kadokawa, translated)