Fire Emblem Heroes (FEH) and Pokemon Scarlet and Violet (SV) are two different games developed by different companies. FEH is developed by Intelligent Systems and published by Nintendo, while SV is developed by Game Freak and also published by Nintendo.
While both games share some similarities in terms of their gameplay mechanics and storytelling elements, they are distinct franchises with their own unique stories, characters, and worlds. It's also worth noting that both are part of the larger Nintendo family, so it's unlikely that there would be any animosity or competition between the development teams.
Ultimately, it's up to individual players to decide whether or not they enjoy the storytelling elements of each game, and whether or not they feel that one is copying the other.
