Not a Snake player but I practice with ^Ralph all the time so I'll give what tips I can on the MK MU.
You want to avoid being on the platform as much as you can. If MK gets underneath you, you're going to get juggled very easily. Early on there are a number of points where you are on a platform, trying to punish MK while he's in the air, by using moves like jab or grab. In these situations, it's better to just get away, get on the ground, and reset to neutral, rather than try and throw out a hitbox.
0:35 He could've killed you here if he Up-B'd, but instead he down-aired. After your grenade throw, it probably would've been better for you to recover straight up instead of towards the stage. Going straight up puts you in a position where MK can't reach you (and thus can't gimp you), while recovering towards the stage puts you in a very gimpable position. Once you've recovered straight up, he has to try and cover your landing, which could either be on the stage or on the ledge, so he has to cover those options.
At 0:37 You should not have B-reversed when you did (I assume that's what you were going for, since you side-b'd instead). I think you were trying to B-reverse to get behind him so he couldn't glide attack you. A better option would've been to either back-air (which would either clash with Glide Attack or hit him) or B-reverse a lot sooner.
0:47 Don't spotdodge when you're techchasing, it leaves you more vulnerable than just standing there doing nothing. The only thing he can hit you with is getup attack, which you can shield. All of his other options are rolls or getting straight up, which obviously can't hit you.
1:03 Not sure if this was a misinput or not, but if it's not, don't try and place a d-smash while MK is still on stage lol.
1:07 After you realised that you couldn't reach the ledge, you up-b'd but panicked and airdodged. In this situation, your only option is literally ride the Cyper all the way on-stage and hope MK doesn't gimp you. MK's best option would've been to grab -> grab release you, but it sounded like he tried to d-tilt or something, so just be wary of MK grabbing you out of Up-b. If you were at lower percents, C4 would've been a good option (immediately cancel the up-b and C4).
1:14 Your spotdodging is impeding your punish game. If you had simply shielded that f-tilt, you could've easily punished with your own F-tilt for a free ~20%, but because of your spotdodge, he had enough time to shield.
1:17 As soon as you saw MK dashing towards you, you should've been preparing to punish the fact that he was dashing. An f-tilt would've been a very good option, or a pivot grab would've been a mixup (which would beat both MK's dash grab and dash attack, his only options while dashing). Instead, you shielded out of fear, which the MK read, so you got grabbed.
1:59 U-air would've been a better option after being hit by that nade. Not sure if you thought you were facing the other direction, but even so, you didn't have enough height to finish the nair (unless you also tried to double jump).
3:06 You should've been dead here, but the MK decided to F-tilt instead of grab for some reason. This is another situation where recovering straight up and being ready to potentially C4 is a good option.
4:25 Finally he grabbed you lol
5:11 You should not have jumped here, you had absolutely no reason to jump. MK got a free up-air and this pretty much led to you losing the stock.
General tips:
Stop forward airing, lol. I know you got like 1-2 kills off of it and a few other hits too, but it's seriously such an unsafe move. I mean if it works it works, but don't try and do it and expect it to hit every time.
Do more stuff with nades. Pretty much the entire match all I really saw you do with nades was either pluck a nade and roll away, or pluck a nade, shield drop it, pick it up, walk a little bit and then throw it forward. MK visibly had no pressure from nades both games, which gives him the freedom to do whatever he wants. Nades force MK to not mash the B button/C stick so they don't blow them up, but if you leave them out/throw them predictably, it's not pressuring him at all. You've gotta mix it up, do some crazy stuff with your nades. Make the MK go "Wait, did he pluck this nade first, or second? Is it about to blow up in my face? Should I try and throw it, or shield just to be safe?" Cook your nades, try pulling out a nade, shield dropping it, plucking a second nade, throw it with the B-throw (don't know the term for it, AKA don't shield drop it) then throw the first nade. The MK will get distracted by the second nade, not realise the first one is about to blow up, and get hit by it.
That's about all I can think of.
