Arslan Senki (TV), Nejimaki Seirei Senki: Tenkyou no Alderamin Recommendations
Both are stylistically, thematically, and topically very similar.
Both anime use nearly identical art designs and palettes. For example, both use the same, historical old-fashioned, font. Artwork is very similar, and scenes are set in similar backdrops.
Both shows are heavily centered around traditional military strategy (for war), and both feature a genius strategist who is a master of war. Both geniuses show more than they tell, consistently proving (through actual battles) their intelligence, creativity, and forethought.
Obviously, the main difference between war in these shows is context. While Arslan features a young prince leading a real revolution against warring
It is only in the beginning of Alderamin on the Sky, but I feel both series have lots in common. Primarily war and intelligent strategists. I am not sure if the development of Alderamin on the Sky is going to follow the same direction as Arslan Senki..