Code:Realize - Sousei no Himegimi, Nil Admirari no Tenbin Recommendations
Both are animes based off of games by idea factory, both have very handsome men, both have female leads who join the male leads with a set goal in mind, in code realize it was to stop isac beckfords terroist plot in Nil Admirai no Tenbin: Teito Genwaku Kitan its to find the evil books
Both anime are set in a fictional historical place. Both have a female lead with a group of handsome men. They're both reversed harem with slice of life but can get dark/serious at times.