Fire Emblem Fates Sales Data
From Media Create:
Fire Emblem Fates: 260,675
Fire Emblem Fates (Special Edition): 42,991
First is both Black Kingdom/White Kingdom (Birthright/Conquest) cartridges. Second is only the special edition, which is one cartridge and presumably one SKU, so it doesn't count as having sold 2 or 3 copies even though it contains that much content.
There was a slight boost in 3DS (mainly New 3DS) sales as well. This only includes physical copies and not digital (there were probably a fair amount of digital downloads as well).
Here are some first week/lifetime sales data for Japan only; I haven't source-checked the data though so be careful about using it for anything serious.
[NES] Fire Emblem: Shadow Dragon and the Blade of Light - ? / 329.000
[NES] Fire Emblem Gaiden - ? / 325.000
[SNES] Fire Emblem: Mystery of the Emblem - ? / 776.000
[SNES] Fire Emblem: Holy War Story - 228.578 / 498.000
[SNES] Fire Emblem: Thracia 776 - 30.104 / 158.695
[GBA] Fire Emblem: The Sealed Sword - 126.267 / 345.574
[GBA] Fire Emblem: Blazing Sword - 109.429 / 265.286
[GBA] Fire Emblem: The Sacred Stones - 146.026 / 246.719
[GC] Fire Emblem: Path of Radiance - 100.357 / 156.413
[Wii] Fire Emblem: Radiant Dawn - 73.337 / 171.924
[DS] Fire Emblem: Shadow Dragon - 147.704 / 252.309
[DS] Fire Emblem: Mystery of the Emblem - Hero of Light & Shadow - 147.045 / 250.592
[3DS] Fire Emblem: Awakening - 262.399 / 469.485
[3DS] Fire Emblem Fates: Black Kingdom / White Kingdom - 353.201 / NEW