Double posting because I don't care!
:07 I laughed, only because this happens to me all the time. "I'mma Z-catch that banana!" *nope*
:15 If Diddy has a banana in his hand, you never want to land with an aerial. By landing with an aerial, you remove the option of reacting to the banana throw with an aerial (and therefore catching it) along with Z-catches, AD catches, and ITs. While you did have a banana in your hand already, you should have just Z-dropped it. Doing this would have, not only have allowed you to get the second banana under your control but would have controlled space making it more difficult for Diddy to punish you in the first place (he'd have to jump over the banana or commit to picking it up before he could punish you).
:20 I don't like jumping here in general since Diddy did have a banana and could punish any landing option as a result. Walking away and then reacting with ftilt would be my preferred option. However, given that you did jump, when you see Diddy flipkick while you're in the air, you want to use nair. It has a constant hitbox out and is more likely to cleanly beat flipkick than fair- which usually trades.
:28 You didn't do an aerial so AZ couldn't react to fair to throw the banana, he had to wait to be able to effectively choose his punish. Because of this, you were able to PS the banana and put yourself into an advantageous situation. I personally would have either SH Z-drop fair'd to start zoning and create pressure since the other banana was above him and he couldn't get to it w/o jumping into your, now dropped, banana and fair. Second to that I would say you should have GT'd straight down instead of forward. Straight down controls relevant space and potentially trips him. Through him gives him stage control.
I'm... really not sure about the fsmash. Even if it was an input error, I can't think of something that would have been beneficial there. With the banana above Diddy's head, getting control of the banana back in #1 priority. If it was an autopilot fsmash after the GT, then the obvious comment to make is to not auto-pilot your options out of a GT and instead react to what Diddy does (if he is shielding, grab, if he jumps OoS, nair/fair, etc).
:35 I'm interested in why you chose to FH fair to get the banana. I don't disagree with it really, and I'll talk about that situation more once you reply, but that decision interests me and I'd love to hear your thought process there.
:50 Diddy was so far away from you, jumping here served no purpose.
You GT throw at Diddy too much- throw bananas up and down a LOT more. They control a lot of vertical space then and you can restrict his movements since he'd have to commit to an action to get the banana or just avoid that area which nets you stage control.
Honestly, that's pretty much it as far as the MU goes. You make the same mistakes almost every time you get hit. I could go through and timestamp each thing, but whatever. It's the same few mistakes you're making over and over, so it should be easy enough to focus on them.
Jump less/in better spots, you're a bit overaggressive when it comes to using DB, zone w/ Z-drops more, etc
You fsmash too much too. If that's the read you want to make, that's fine, but I'd use ftilt there. It won't stale your kill move, hits at a slightly different angle, the hitbox goes in a different direction so when the hitboxes are where is slightly different, etc.
You struggled really hard to kill him 1st stock, staling DS a lot in the process. You need to work dsmash into your game.
If you want me to touch on any specific part of the match/MU, I'd be happy to do so. In general, a lot of your damage just came from hasty/bad landings.
Like I said, usually I'd be more detailed, but I don't feel like C/Ping the same comment with a different time stamp is all.