Reviving this important thread. All matchups are for a tiny 2122 Brawler. + means we win, - means we lose, = means it about even.
Vs. Sheik: =
Vs. Falcon: +
Vs. Link: +
Vs. Marth: -
Vs. Lucina: =
Vs. Samus: -
Vs. Roy: +
Vs. Mario: -
Vs. Luigi: -
Vs. Sonic: =
Vs. Rosa: -
Vs. Mac: +
Vs. DK: +
Vs. D3: +
Vs. Bowser: +
Vs. Puff: +
Vs. G&W: +
Vs. Diddy: =
Vs. Pika: =
Vs. Villager: -
Vs. Doc: +
Vs. Ganon: +
Vs. Zard: +
Basically, Brawler dominates characters that are easy to get in on and combo to death (Donkey Kong), but loses to characters that can keep him out and aren't easy to combo (Samus). I don't think Brawler loses any more matchups than I listed here.