KirbyKaze
Smash Legend
I dislike using the best players as a representative of matchups because then we can say all the Marth players lose to Armada, ergo Peach has the advantage over Marth. That's completely insane. Armada is also the best Peach by far and he's beaten the indisputably best Marth (Mew2King) several times.... -_-
Mango only lost to Kage once after getting drunk, while Amsah has lost to Zgetto, Remen and Lucky, as well as dropping a game to (I believe) Pasi from Germany. Amsah exclusively mains Sheik and is the best by far. If you want to look beyond him, Captain Jack lost to Masashi a lot.
As for Jack and whatever losing to Masashi, that was like... 4+ years ago? I don't know how relevant a dash attacking, FJ Nairing Fox style is in today's CC-heavy gameplay.