Oh god, DDD...
Be extremely gay. That ******* is just going to stay in his shield all day waiting for you to try and smack him with your limited sword range. Spam the hell out of him, his Waddle Dee army is nothing compared to your projectiles. Rack up as much damage as you can, and then move in with Zair as an approach and finish him off. For me he's a lot easier to kill when he's in the air using the delayed up air tactic, but if he's at the edge at around 130%ish and you believe you can forward smash him, go for the gold.
As for Metaknight...well, it's not going to be easy, man. Everyone hates Metaknight. Always keep a bomb on hand. Like what I'd do is shoot an arrow, pluck a bomb, fire another arrow and maybe a boomerang. Keep in mind when the bomb is about to explode and throw it. The reason you have to keep a bomb on hand is in the event that your MK opponent is a Whorenado spammer. Bombs stop the Whorenado. If you're above him while he's using his Whorenado, down air is good. Besides that, it's going to be a tough battle. Using your projectiles to rack up damage and see if you can spot openings. Never underestimate Metaknight's range...always assume the worst. When Metaknights are in panic mode down smash mayhem begins, so don't get too close. Just weave in and out.
I hope that helped in some way. ^^; Good luck at your tournament. Make us proud.