less rolling and vary your approaches you were getting punished for a bunch of those dash attacks. when he's actively jumping over you or shielding whenever you rush him because he thinks you're going to dash attack (which you inevitably do) that's a sign that some aerials or shielding or something OTHER than dash attack is in order. and the answer is not d-smash, which you do a few times. d-smash you do if they spot-dodge. if they jump or shield... well, you'd probably use an aerial for the former and grab for the latter.
your movement seemed really limited. it was basically dashing and rolling. you need to be more mobile and less constricted in your movements, either you were rolling behind him, rolling away from him or dashing at him.
edgeguarding seemed sloppy.
i think your general gameplay on platforms was lacking. i think platform dropping aerials and wavelanding off platforms into aerials is a huge help for sheik and you made very limited use of it. it's awkward to implement at first and obviously you need to work on your approaching game and edgeguarding before platform tricks, but you seemed glued to the ground the entire match, which made me cringe. you have to be more mobile and add some variation.
i'll point out specific stuff on note in vid later.