Simikins
Nerfed
Set 1 VS Gunblade:Here are some matches I've lost:
https://youtu.be/HjcL6tuFJwo
https://youtu.be/bjLRv11A-w8
https://youtu.be/0VW9wTOa7dM
I've noticed that you've been going for bouncing fishes to finish off your fair strings, and they aren't connecting, putting you in a bad position. Either do a bouncing fish after the first fair, or finish the string with an up air.
You are also throwing out a lot of smashes, when a simple tilt would have been safer and more effective. Be careful with that, because over committing will cost you damage.
Beware of jumping too much at kill percent, as characters like mario can just upsmash and take you out.
In your position, I'd be throwing more needles and forcing him to approach, as mario's approach isn't very good.
You have a very aggressive play style, but sometimes you need to hang back and be more careful.
Set 2 VS Dugan:
Fox is a fast faller, juggle him!
You were doing a lot of unsafe things, running up and grabbing randomly, charging at him, etc. When it works, it really works, but when it doesn't it really doesn't. Sheik has the ability to play very safely with high reward, abuse that!
Also, make sure to learn all of sheiks combos. BNB isn't always enough on it's own, you have to know the situational stuff. For example, at 5:44 that was a Void combo! You could've killed him then and there. Or even if you didn't have a full needle charge, that would've combo'd into BF.
You were playing quite reckless that set, and it cost you.
Set 3 VS Dugan (Winners Finals):
You're movement was what let you down in this set when you were playing as mario, but I'm assuming you want feedback on the sheik game.
Similar to the other 2 sets , you are overcommitting a lot. Just going in straight for a grab isn't always a good option. You were getting punished hard for charging in. You need to space around more, utilize tech such as dance trotting and C-bouncing. Also don't be afraid to reset to neutral.
Overall:
Know your options - Learn the situational combos sheik has, like her needle combos and Utilt combos.
Don't over commit - Bait your opponent out, don't always just charge in.
Neutral - Work on spacing and movement.
Hope this helps.