I haven't played those, so I'm going off what I can learn about them in a reasonable time frame.
A contemporary review of the first Fire Emblem game to release outside Japan shows one reviewer referring to it as "turn-based strategy" at the same time that another reviewer (writing in the same magazine, possibly cooperating on the same review?) says it's a "tactical RPG". That second description matches the uninformed impression I had of the series and also matches how it's described on Wikipedia. Plus, this isn't exactly an early usage - Fire Emblem first released in 2003.
Nobunaga's Ambition seems like it would fit perfectly in a genre defined by Civilization and Empire; I'm not sure why you're saying it's not a 3X game? And the same appears to be true of North and South.