LOL why me?
At any rate, it's kinda hard for me to give advice because, to be blunt, you seem like you don't even have the basics down, really. For starters:
-Work on your execution; I'm seeing a lot of random dairs and stuff that I assume were supposed to be other moves.
-Be more compact; don't jump around swinging your sword so much, focus on your ground game.
Stuff specific to Young Link:
-There's really no reason to powershield in this matchup because frankly his projectiles aren't that scary. Unless he gets you in the air, mostly everything he has is easily defeated by CC'ing and WD'ing out of shield.
-I am seriously going crazy over here watching you try to edgeguard with fsmash. Toward the end of the second match, you were literally letting him recover for free. JUST DTILT.
-If you hit them far enough away that they have to use the hookshot, grab the edge, drop when you see the air dodge, and double jump bair when you see the hookshot. Alternately, you could avoid the hookshot with ledge invincibility and just stay on the edge, which will cause them to pop up when they retract (because they can't grab the edge if you're already on it). Then you can ledgehop > stuff.
-If they throw a boomerang on the ground and you shield it, 90% of the time they'll immediately pull a bomb. You can punish this for free with WD out of shield > stuff. Obviously adapt if they start doing something else.