Sorette Douka to Omoimasu! ~Teshoku Joshi, Black Kigyou de Survival suru~

Wako (35), a woman born in the Showa era who has lived her life with drive and determination, and Wakana (23), a woman living in the Reiwa era who wants to achieve results smartly and with an emphasis on time. The two, who are complete opposites in common sense and work attitudes, meet as colleagues at a startup company where they change jobs. However, it turns out to be a terrifying black company where power harassment, sexual harassment, and monster employees are rampant...!!

Source: Anilist