Kirby vs. Falco
The difference in this match-up changes wildly at different levels of play. When the Falco player is at a low level of skill, Kirby is a very challenging opponent capable of dealing massive combos and powerful attacks. As the Falco learns the match-up, further explores his options, and develops counter strategies against Kirby, the match-up starts evening out into a much more neutral challenge. At high levels of play, Falco's attacks and mobility give a distinct and obvious advantage over Kirby.
Long Range
The best thing Kirby can do at this range is Crouch. Do not even bother approaching. If Falco is smart he will not bother approaching either. If Kirby wants to eliminate a possible approach option from Falco, he can roll to the edge of the stage which makes Falco's Side Special unfeasable. At this point, it is up to one player or the other to approach or to try to force an approach. This will mostly be from Falco because Kirby really can't do much except squat there.
Alternately, here is some advice should Kirby which to approach Falco or force an approach from Falco. It's inevitable that Falco will be putting up a wall of lasers between himself and Kirby to make approaches more difficult and to gain a percentage lead should any of the lasers hit.
Kirby actually has a number of options while approaching. He can use the universal defenses against incoming lasers such as Shield and Dodge, specifically you want to Perfect Shield since Dodging (air dodge/spot dodge/rolling) is a bit more unwieldy, frame-wise. Other options include ducking under lasers during the approach (just crouch every time a laser is fired), as well as floating over the lasers with multiple jumps. An aerial approach can put pressure on Falco since the opponent will likely be expecting an attack (i.e. B-air), and can shut down the lasers early as the Falco prepares to defend, intercept, or Illusion away any perceived attacks. Note that multi-jumpers such as Meta Knight employ an aerial approach when dealing with Falco's lasers and grab game.
Mid Range
Falco can take a lot of advantage from this distance, his Lasers are as viable at this range as at long range and can be used for leads into Jabs, Tilts, Grabs, Dash Attacks, and Smashes. Retreating Lasders also allow Falco to pull back and distance himself from Kirby should he need it.
While Kirby has some things he can attempt at this range, most of it can be shut down by a pre-emptive Laser or one of Falco's fast attacks. Of most importance at this range is Falco's use of his Side Special. This attack's use is in its ability to simultaneously move Falco out of Kirby's range and deal some damage. The damage is slight, but when combined with Lasers it allows a nearly unpunishable strategy for Falco to build damage. Additionally, it can force Kirby into a defensive position which can give Falco an opening for an approach, specifically moving into close range for a Grab.
Close Range
Both Falco and Kirby have strong grab combos on each other, so a mistake at this range when at low percents (under 20% to 30%) can result in a good deal of damage being dealt. If Falco gets a Grab on Kirby he can chain grab with {D-throw(9%), Grab, D-throw(9%*), D-air(13%)...}:31% and still have a solid follow-up for additional damage which can leave Kirby at 30% to 60% damage.
If Kirby gets a Grab on Falco he can get a guarenteed {F-throw (8%), U-air (10%)}:18%. Kirby can continue the combo for further damage but it is dependant on the Falco player's ability to S-DI out. If the Falco does not S-DI out of the combo, Kirby can follow-up in a few ways, the most common ways being {F-throw (8%*), U-air (10%*}:18%*, or {(r.)U-Tilt (7%), B-air (12%)}:19%, both of which have possible follow-ups. In total, Kirby can score 18% to about 36%* damage.
*possible reduction due to Stale Moves.
KO Options
Kirby definitely has the stronger KO options. His F-smash is very effective against Falco due to its powerful horizontal knockback. Since Falco is susceptible to horizontal KOs, the F-smash can kill at around the 100% levels.
While Falco's KO options are not as strong as Kirby's, his U-smash can still be a very strong KO attack because of Kirby's light weight and because he is susceptible to vertical KOs. It is also a fast smash attack and the distance can be increased with a DACUS making it easier to hit with and usable from much farther away.
Edge-Guarding & Recovery
Although Kirby has a huge advantage against Falco off-stage, he faces a couple main problems. First, it can be difficult to get attacks to land on Falco in order to get him off-stage to begin with. Second, even when off-stage, Kirby will be unable to move quickly enough to follow Falco off and continue the offense before Falco can recover.
Most often, Falco will not have much trouble getting back to the ledge quickly, and if Kirby is Edge-Hogging, he can return to the stage with very little landing lag to be punished. If, however, Kirby can get Falco to recover low enough, he can **** Falco's U-special recovery. There are also a number of attacks that Kirby can use against Falco's Side Special should he choose it to recover onto the stage. F-smash, D-smash, U-tilt, B-air and N-air all have uses against an in-coming Illusion.
When the roles are reversed, and Kirby is being edge-guarded, Kirby no longer has a big advantage against Falco. Instead, Falco has enough options to use against Kirby to make his edge-guarding a threat to Kirby. Falco can send Lasers at Kirby from a distance, he can use B-airs when Kirby gets close to the stage, and of course he has his D-air which can spike Kirby's slow jumps or even spike him out of a Final Cutter.
Match-up Specific
Falco is very easy to juggle and combo making Kirby's U-tilt, U-air, and F-throw effective at building damage. Falco's Lasers are one of - if not the best - Copy Abilities in the game. They cannot be spammed at Falco, but they can be weaved into Kirby's attacks and can help create openings, build damage, and interrupt Falco's attacks. If Falco chooses, he can play a distancing game the entire match and there is little Kirby can do about this.
40-60, Falco's advantage
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