Fire Emblem is far more appealing for the west IMO. Tactic games work well, the shift to a more "easy to play" experience made Awakening a far less "obscure" game, the new art style from the 3DS games looks less a 90s anime and more like what anime fans like nowadays... And it's not popular only between weebs, the gameplay is addictive and deep, and even if I despise the new marriage/child mechanics, some people really like to min/max using these.
And yeah, Nintendo clearly knows how to market and sell the games on all the markets.