I've been finding that F-tilt pivot works as a quick way to turn around and start lasering. F-tilt is only like 10 frames long, such a fast move and Fox slides so much with his pivots.
is alright. I used to john about the matchup a lot, took me a few times to get this matchup right. You have to basically bait him into doing something punishable (watch out for his smash attacks though, they have super armor) go in and get him in the air (Fox has tons of moves to do this), then bait the counter or air-dodge once he's in the air and keep popping him up. It's pretty annoying because you can't be constantly on him, you have to run in and out (otherwise his faster ground moves will mess us up).
It's tough because Fox won't have a solid way sans our B-air, F-smash and D-smash to get him off-stage successfully, which means Little Mac will build his KO punch meter with all the damage we give him. I think this is what makes him hard, the fact that we play a damage-racking combo character vs a character who gets rewarded for getting hit x_x
is on the same boat, except I think he's much worse than Little Mac. If he's at 140% and we're at 45%, both of us are in KO percentage. Luckily, Lucario has some laggy moves that we can abuse, specially if he lands onstage after his recovery. When you have to chance to do quick punishes, a falling N-air and dash attack work wonders to push him in favorable positions in front and above us respectively, dashing in and grabbing also works if you see him fall from an unsafe aerial onstage (just be careful of Force Palm or other moves like those, so much hurt). Stop building damage once he hits ~115%, nothing will combo into Fox's KO moves if you do that and he'll be hella hard to KO.
Here's how to beat him: use Down-B. 3/4 of Mega Man's moveset is instantly useless.
Ok, jokes aside, it's obviously not that simple. Mega Man is an extreme zoner though, but just Down-B won't win you the match. While you should be using the reflector occasionally (ie, don't become predictable with it), you should be avoiding his linear projectiles (they all travel in straight angles). You can shield his Crash Bomb, pick up / grab his Metal Blade, and just jump away from the Leaf Shield. His jabs are pretty annoying though, a good Mega Man will try to zone you out from a mid-distance with short-hops, shooting in front of him in the ground and at SH jump height. Pretty annoying to get close to him, shielding at the right moments is key in this matchup. Once you get close to him though,
stay on him! He'll try to rush coil his way out, and if he does that's ok but just chase his air movement from the ground and keep him up there. Fox capitalizes a lot in keeping his opponent in the air.
If you see him charge his F-smash (the Charge Shot), just press down-B right in front of him for a free stock.
These are just some matchups.