I havent watch the video yet i'll watch it later, but betweem the things that really work against a falco.
-f tilting: this is really really good option because in some scenarios, you can wd or wl to ftilt, and then follow up with another ftilt.(the first ftilt has to be an upwarded ftilt, and the second a regular ftilt if you really want to push them far off the stage. This also works with the lasers. Sometimes when they are running towards you, an upwarded ftilt will stop them from shooting when they want to grab you after the laser stun, and is also good to sometimes get hit by the laser, and use the ftilt as it eas ganons jab.
-throwing game: in this matchup, grabs are really really important, because you can either do combos out of them, or positionate your opponent (falco in this case) where you want them to be. Normally this isnt as easy as it sounds when you are playi g a really good falco, but i knkw the chances of grabbing are aaaalways there, up to you to take them or not, but grabs are luigi's butter.
- shielding: in this matchup, its not safe to go for the shield grab a a lot, so what you want to do, ks play with the falcos mind, and make him feel he cant adapt when you are on your shield. You see, you will vsriate from light and heavy shield between his pressure momentums. Light shielding is really good because luigi does not get poked of the shield, something that happens a lot with the heavi shield, and besides, if you get hit on your light shield you will be pushed away and automatically off pressure. You wkll use the heavy shield when you think you can react with something after you get hin on your shield. It can be bair oos, or nair oos, upb oos, waveshield back, or just shield grab.
- the oos game is really imports t also in this matchups, brcause coming out of a shield with an aerial its going to almost always hit, and this part of the game its a lottle bit tricky yes, but thats why you gotta keep using different shields in differents moments of pressure, so he is never sure of ehat you are going to do. When getting hit in the light shield, is a good idea to after beeing pushed away a little bit, wd oos in place, and dsmash/ftilt them.
I practiced the power shield a lot and i get 3/5 at least, this helps me a lot too, idk if u can practice that. Lucks lucks