Without reviewing hundreds of movies the Subway Fight in The Matrix is my choice.

Alternately, the fight in Seven Samurai where the sword master is introduced.

Animated? The fight between Motoko and the puppet terrorist stands out, as it emphasizes a lot of the themes of the story; Invisible, super strong, and super-capable, Motoko completely and effortlessly defeats the puppet terrorist despite his installed martial arts abilities. He simply cannot meaningfully fight her, and when the fight is over she looks on with something like alien pity.

Oh that fight when Algren groks his sword training in The Last Samurai and defeats like four guys in the dark is really cool.

Oh, the fight in Pirates of the Carribean where Jack manipulate's Legolas' academic but inexperienced fencing to get to the other side of the room in an attempt to leave without hurting him. it says so much about who the characters really are. You get an early hint that Jack is much smarter, more capable, and more aware than his goofy persona suggests, and also of his weird humanism; He's no one's enemy, he just wants to go his own way. Plus that line "People arent' cargo, mate" is a great encapsulation of humanist philosophy, and you can extend it to anti-capitalism if you want.

The hospital shootout in Hard Boiled fucking rules. There are probably a bunch of John Woo scenes I could mention though, like the shootout at the beginning of The Killer that sets the whole story into motion, which has incredible choreography and emotional impact.

@SorosFootSoldier@hexbear.net already mentioned Police Story, so I'll just second it.

Kind of primitive by today's standards, but the duel that introduces Kyuzo in Seven Samurai is cool as hell (for some reason I can't find it unedited on youtube, so just watch the movie).

Car Chase scene in The French Connection- William Friedkin was firing on all cylinders.

Not really a single scene, but I love John McTiernan's very slick and interesting way of directing action in the 80s, with Die Hard and Predator. His action scenes are tense and almost like horror scenes, particularly in Predator.

There are lots of James Cameron action scenes I could list, so I'll just say the police station shootout in Terminator, and Ripley fighting the Alien Queen.

I'm also personally fond of the final sword fight in Rob Roy.

In animation, I think I've got to mention the fight between Aang and Katara versus Azula and Zuko in ATLA, for the animation quality, creative choreography, and story impact. As a kid I loved how it ended the second season on this massive defeat and tragedy, which reminded me of Empire Strikes Back. I could mention a ton of scenes across all of Avatar but that's my favorite.

Church shootout in Cowboy Bebop

When I defeated Toad at the Statue of Liberty.

well I came in here to say "basically all of Fury Road" so looks like my work is done

Still impresses me as an adult, but the first time I saw this jump in Police Story was crazy

The hallway fight scene in Old Boy is my kneejerk reaction, but the hospital fight in Hard Boiled and the stairwell fight in The Raid is pretty good. Assault on Precinct 13 as a whole is pretty close to one long action sequence.

RRR Tiger fight

The rainy courtyard scene from Hero is a favorite of mine, tied with the very famous dojo scene from Crouching Tiger Hidden Dragon.

Much sillier and artsy fartsy compared to a lot of the stuff in this thread so far but I can't help but love how perfectly constructed they are.

Ichigo vs Byakuya on the cliff over Soul Society from Bleach is my formative hype anime fight.

For live action, it's gotta be the opening of Ninja 3: The Domination, where a ninja kills like two dozen cops in a row.

Roddy Piper and Keith David fighting in an alleyway for like 15 minutes straight in They Live

I guess heat. I rewatched it recently and both heists are incredible.

The shootout in true detective season one with clan in da front playing in the background.

As for anime ones, luffy throwing crocodile into the sky while Dvorak's new world plays.

The Katara/Zuko/Azula showdown is pretty bloody good

#1 is two scenes, but blues brothers car chase into huphuphup

https://m.youtube.com/watch?v=2quc-iQ96R0

https://m.youtube.com/watch?v=8VFIPCpocLk

#2 is the toilet fight in breaking bad because it's funny

flcl has great action animation

Old boy. Fight in the elevator/hallway

The Matrix, which is heavily anime inspired. I guess my favorite sequence is the subway station fight.

Fight scene at the beginning of watchmen

Battle of the bastards in game of thrones

It's hard to pick just one as a favorite so I'll mention a few that haven't been mentioned.

Strange Days, specifically the scene where you find out what happened to Jericho One.

The opening heist/chase from Drive is a great example of music setting the tempo and the tension.

The big apartment/stairwell fight from Atomic Blonde which is fantastic because they actually show the combatants getting exhausted as the fight drags on. Fantastic change of pace from the usual frenetic stuff. You're on the edge of your seat screaming "GET UP!" at the screen.

The colony attack from Aliens when the power gets cut and the emergency lights kick on with that eerie red glow as the motion trackers count down until all hell breaks loose.

The opening battle from the Macross movie Do You Remember Love with the low gravity flight physics and the fantastic music I can only describe as "Battle Jazz"

Honorable mention to tank chase from Goldeneye because it's got a fucking tank in it.

Kill Bill: Volume 1, The Bride vs. The Crazy 88.

Wick vs Ares CQC in the hall of mirrors at the end of John Wick 2

Gogeta vs Broly in DBS: Broly is great just for the pure spectacle of the animation and the soundtrack and all. Complete slop, great action.

Kill La Kill has one of the best opening scenes I've ever seen in an anime, with Gamagoori just busting down the door and setting the tone for the entire show. It's not nearly as technically impressive as something like Broly, but the role it plays for the pace and themes and everything of the story while still being incredible action makes it a standout example for me.

Seconding Blues Brothers, Hard Boiled, French Connection... You gotta give props to the Mission Impossible series, but I felt like the most recent one was just a little too broad. Ronin and Jack Reacher had great car chases, too.

I don't watch a lot of action movies, but there was a period when it seemed like my friends always had Michael Bay movies on. Dog shit action sequences, pure trash. I kept falling asleep, which is not the ideal reaction to an action movie. Then I saw the first Jason Bourne movie, and I was like, "oh, an action sequence actually has drama if you can tell who is hitting who and you know if you should be going, 'get his ass!' or sucking your teeth." So idk, that movie probably doesn't have the best fight scenes ever, but they're memorable to me by contrast.

Despite the rest of the movie being awful, the sled chase scene in Pathfinder. Also props to the scene on American Dad where Roger gets a faceful of cocaine.

For games, the final fight in Death Stranding was just exhausting, tiring, wretched in a way that real fights can be and much media fails to ever capture.

The final sequence in the first Stalker left me so drained after I finally made it to the other side it took me a day to really recover.

Blade and Sorcery's 1.0 boss fight is incredible for what it accomplishes. When I realized I was entirely upside down it hit me that this was something really new that only vr could do.