I really enjoyed the first season and can wholeheartedly recommend it.
The mystery of the Chaika's, who suddenly appear several times and have very different characters and abilities, is interesting and when the main protagonist has to decide between the red and white Chaika, there is real tension.
Season two - I enjoyed the first 4 episodes. But then... dunno... I kind of lost interest and fast forwarded a lot.
The obscure main plot - a mad emperor who is reincarnated and seemingly omnipotent - kept coming to the fore... and I couldn't relate to it at all.
The Chaika's are coordinated by a seemingly omnipotent sorceress who keeps appearing and then disappearing out of nowhere. Nobody can harm her. No explanation is given for this kind of magic that no one else has. In general, world building is lacking, and the occurrence and properties of magic and the past of the world and characters are not properly explained. Towards the end of the anime, the plot just seemed random and boring to me.
Season one I would rate 7-8. Season two 4-5 max.