I was skeptical about the datamine leak thinking it might've been some overdue April Fool's joke, but a bug in Classic mode for the 3DS where you fight Kirby characters on Battlefield leads me to believe that the leak is in fact legit.
Reddit threadI can definitely see Ryu being chosen as a third party (in spite of SFV being a PS4 exclusive...), but Roy strikes me as a really odd choice, primarily because him having a fanfare file points to him being an entire character, rather than say a costume of Marth with ph1r3. For those that don't know, every unique character has their own fanfare file, even though many are identical (e.g. Mario, Luigi, Peach, Dr. Mario):
snd_bgm_Z01_F_Mario_3DS
snd_bgm_Z09_F_Luigi_3DS
snd_bgm_Z13_F_Peach_3DS
snd_bgm_Z60_F_MarioD_3DS
However, alternate characters like Olimar/Alph and the Koopalings share the same file:
snd_bgm_Z25_F_Pikmin_3DS
snd_bgm_Z70_F_Koopajr_3DS
With Roy, I can't help but think:
-"another Marth?"
-"another 'Roy'?"
-"another Fire Emblem character?"
-"isn't Roy one of the worst lords in the series?"
-"why do they care about Roy again if he has nothing recent coming out? Are they going to announce a localized Mother 3/Binding Blade Virtual Console port or something?"
Sakurai has been confirmed to be making an appearance at some Fire Emblem 25th anniversary event.
Link RoyEDIT: I should also add, Smash 4 uses the same filename convention of Brawl, and that the unused Mewtwo and Roy fanfare in Brawl is actually
different from the patched ones:
snd_bgm_Z38_FMYU2
snd_bgm_Z39_FROY
snd_bgm_Z80_F_Mewtwo_3DS.nus3bank
snd_bgm_Z81_F_Ryu_3DS.nus3bank
snd_bgm_Z82_F_Lucas_3DS.nus3bank
snd_bgm_Z83_F_Roy_3DS.nus3bank
For further reading:
https://sourcegaming.wordpress.com/2015/04/18/all-about-ryu-and-roys-files/