The Fire Emblem and Shin Megami Tensei crossover game, Tokyo Mirage Sessions ♯FE, was originally going to be a crossover between Pokémon and Fire Emblem. There were actually no initial plans to add the Shin Megami Tensei characters into the mix and game director Kaori Ando felt the Pokémon and Fire Emblem series’ RPG mechanics were pretty well in line, and that a crossover could work. However, the plan was not executed. “Though I agreed with her,” said producer Hitoshi Yamagami, “by chance the Pokémon group had already proposed what eventually became Pokémon Conquest at the same time.” Tokyo Mirage Sessions ♯FE was released in 2015 for Wii U.
Source: Game Informer