FIRST VIDEO THOUGHTS:
Your mixups and crossups are pretty good. You are good at putting yourself in unpredictable spaces around your opponent. That being said, instead of trying to control space, you throw out strange, pointless moves a lot of the time that allow your opponent to gain ground. You have a rolling problem that your opponent should be punishing harder than they are. You dropped a couple of combos but nothing too bad. Be careful with rock. Don't try to mix up with it as much, and definitely don't just throw it out (again, throwing out moves for no reason in the neutral). Use rock when you know you're going to get hit. Get a stronger idea of Kirby's priority. You're getting trades and beaten by things you shouldn't always be. Some of your mixups (like with dangerous hammers and stuff) get stuffed because literally anything they do beats it. You're getting followups on dash attack and dthrow stuff that you shouldn't be getting because he's not teching. You tried dash attack to fsmash a couple times (along with dash attack to hammer) and with real DI that's not a thing. Dash attack to utilt is a thing. Actually utilt is really good please use it more. Same with neutral air. Your crossup game is really good but I would like to see you get more shield pressure/pokes out of your crossup game, like with bair or even late dair (you wont get shield grabbed). Your grasp of fast fall fair is very very good. You try to fall onto people with Rock a lot and then bust out right above them, which seems like it would work, but only if they shield. Unfortunately he is just throwing out attacks every time (not to mention the popout animation with rock is so long and easy to react to). So yeah dont pop out of shield right above their head. Kirby's platform drop game is dope with bair and sometimes nair. You could have punished Peach a couple of times (look at like 3:40ish where Peach does a dsmash under the platform. You could have dropped through with fast fall fair and grabbed). Also, right after, dash attack to hammer only works if they DI ****ty. There are a couple times when you could throw out bair or something and you just did like fair or something that wouldn't hit in that situation. In general you throw out a lot of nonsensical moves that couldn't hit, when you could easily just throw out a hitbox actually in their direction to get them. Utilt through platform is stronk pls use. OOH very good juggles when you knew Peach didn't have her second jump. Watch out, though, as there were a couple of times when the Peach could have traded with you hard with Peach's nair or possibly dair.
In general, your movement is strong (but stop rolling and stop doing aimless Side Cutters). You need to be more reactionary in the neutral game, and focus on controlling your opponent's space. Don't throw out random moves in the neutral that just waste time for you and don't put a hitbox anywhere near your opponent. Your punish game is good but needs work. Just figure out what can go into what. Don't try to do so much hard read stuff that depends on them picking from a limited pool of options. Figure out what could cover the most options. Like, don't dash attack to hammer, trying to rely on specific DI. Don't return to stage with hammer every time, trying to rely on them edgeguarding a certain way. Don't break out of rock right above them, relying on them shielding. Work on your platform drop game. Utilize inhale for shield pressure. Utilize dair for shield pressure. Work on crossups with dair and bair. Use nair OoS and work on it as a safe poke/approach option. Work on figuring out when your opponent is open (like Peach right after that dsmash) and find the fastest way to punish (fast fall fair through platform into grab) and work on the punish game itself.
So far though you're looking strong! You have an understanding of a lot of his moveset and you are in general conscious of the space around Kirby. just iron out those kinks and reevaluate the uses of your moves and reevaluate your situational options.
Will watch the other videos later!