Senjou no Valkyria, Shirogane no Ishi: Argevollen Recommendations
War between two countries. Main characters are part of military squads. Their squads accomplished many impossible missions and and earned great reputation. Also both squads have very powerful secret weapon (robot in Shirogane no Ishi: Argevollen and tank in Senjou no Valkyria: Gallian Chronicles). However time is different. Shirogane no Ishi: Argevollen is in future (not so far from nowadays, their just have primitive robots) and Senjou no Valkyria: Gallian Chronicles is in past, about WW I.