Oh oh oh, since it was never brought up...
Back at launch, all the Marths had really janky animations on their back-airs. Chrom and Roy especially: their arms didn't pivot anywhere but the wrist on the back-swing, so it looked like their forearms were made out of brown paper bags being twisted 360 degrees. It only stuck around for a few frames, but it still looked absolutely terrible.
Then, to my surprise, the 2.0 update actually fixed the animation, so their arms aren't horrendously contorted anymore! On top of Chrom's victory theme being fixed, it makes me really happy that they're taking the time to polish up all these little aesthetic details that got glossed over at first. They're really trying to make this game the best it can possibly be. You didn't see the updates fixing this minor kind of stuff back in Sm4sh.
(now they just gotta fix how janky Chrom's cape is and he's good to go)