He analyses historical European novels is correct. There is no need to add an s to the word European; anything that belongs to or comes from Europe is European.

He analyses European historical novels. novel = a type of fiction historical novel = a type of fiction set in a historical setting Chinese historical novel = a type of fiction set in a Chinese historical setting European historical novel = a type of fiction set in a European historical setting medieval European historical novel = a type of fiction set in a medieval European setting

https://www.gingersoftware.com/content/grammar-rules/adjectives/order-of-adjectives/ English has a set order of adjectives. We cannot vary it. Ever. Let me know if you can't work it out.....:)

It depends on exactly what you are trying to say. It could be: Historical Europeans' novels = The novels of historical europeans كُتُب الأوروبيين التأريخيين Europeans' historical novels = novels that Europeans wrote about historical subjects كُتُب الأوروبيين التأريخية Historical European novels = Novels from Europe that are historical كُتُب أوروبية تأريخية