Ok so.....out of the 8 replays I had saved from my matches yesterday with
Gemneye
only TWO of them were short enough to upload to Youtube (Nintendo why 3 minute limit ;-; ). And the 2 that I did upload were not really the best ones for critiquing purposes since those were the only matches where he used Roy and Fox and I take it he's much less familiar with them than he is with Robin and Marth (also I feel that Delfino Plaza kinda screwed him out of a stock). The ones where I was Falco, or he was Marf, or the Robin dittos would've been way better. But I did send you one of each of those Gemneye so you should at least be able to review those yourself (iiiiif you didn't save them yesterday). I'm still going to post those 2 with Roy/Fox though in the hopes that maybe everyone else can maybe provide something useful from them.....
Also Create Highlight Reel kinda sucks, I tried using it hoping it'd cut a video down to just under 3 minutes and still be somewhat useable......
it made it 50 seconds long fml
Anyway, now that I've watched them I can give you some feedback, mainly from the replays that I
wanted to post.
The first thing is Jab. You use it an awful lot with

but less so with

. The Falchion's jab is good to set-up guessing games, but is kinda not great outside of that. You wanna use Ftilt/Dtilt more. Robin's jab on the other hand is one of the best in the game and is one of her best options at close range; it's sweet, disjointed, frame 4, damage racking+killing, frame trap goodness. Her tilts on the other hands are sub-par. It hurt you in particular when I was using

. Falco is a fastfaller, and Wind Jab annihilates fastfallers, which you can see in the Fox video above (I got like 25% offa one of those). I think you only ever used Wind Jab on me like once, and then you kinda held it too long and I was able to slip out before the final slash. I'm not 100% sure this is how Robin is supposed to deal with the bird man, but I'm pretty the basic idea to fight him is to try and keep him out since his mobility is very average, and capitalize on mistakes with Wind Jab and the Levin sword. While he's not

,

, etc, Falco is still skilled in hand to hand combat and that's where Robin loses in the matchup (his Jab is also frame 2). It can be a little hard to zone him out because Blaster and Reflector (and admittedly I maybe should've tried to pester Cardinal with those to try and get him to approach instead of trying to rush him but oh well), but it's still very much do-able.
There was also your usage of throws. You're fairly good at getting grabs, but the problem was what you did
after the grab. Marth and Lucina's throws are weak and offer little reward, but you can get more out of it with their above average pummel (if you remember the Lucina vs. Dedede match, I almost always pummeled you a bit before throwing). And with Robin you seemed to be awfully slow at following up on D-throw and/or would do the wrong follow-up. Though I sometimes use the wrong follow-up too, so....
The one other thing that stood out to me was that I don't remember you ever really attempting to edge guard. It's not as easy as some people make it out to be *cough*thatoneguyinthegeneralcompetitivethread*cough*. Some characters aren't exactly suited to off-stage edge guarding/deal with your (get up) options much better on stage, and some characters you just don't bother trying because it's a low chance you'll do anything significant. But there are some simple things you can do with Robin and Marth to at least edge guard a little, which should help a bit, like dropping an Arcfire or two at the ledge, trying to hit them with Elwind off stage, run off Faris/Baris, etc. You also would sometimes over-read/over-anticipate my get up and try to preemptively hit me (and honestly I sorta do the same thing with Elwind anti-juggles) and I was able to get a few punishes from that.
.....that's all I got, there may be more to it than that, my assessment may not be entirely accurate, but I hope it helps a bit.
Tomb of the Giants sucks