Hulk = Saddle Rager
Captain America = Miss Marevellous
Thor = Zapp
Scarlett Witch = Radiance
Quicksilver = Filli Second
Iron Man = Masked Matter Horn

Earth 616 versions. I think It would last a maximum of a minute.

4052347 The avengers would beat the crap out of them in seconds because they don't have to hold back for a TV Y rating.

Honestly, I think they would just team up and kick Doctor Doom/The Mane-iac's ass!

4052347 4052348 Yes, the Avengers have fought gods like Loki and Thanos. They have the Elements of Whoop-Butt. Discord was close to a god of chaos, but he was foolish and easily beaten with the Elements of Harmony. I don't know if that would work on Loki or Thanos.

The question isn't in how long they would last, but what would be left of the planet after the equivalent of TWO Earthbreaker hulks.

Who is the other Hulk? Because Saddle Rager is nowhere near a planet buster.

4052347 yeah the avengers would win they can actually work as a team

4052347
4052348

One problem. The Power Ponies are free to operate on Cartoon Logic (eg, I can do anything if it's funny), while the Avengers have to stick to Real World Logic. Plus, I have a bit of faith in Rainbow Power, since it's basically Super Saiyan, Pony Style. Of course, I won't underrate the Avengers, either; I'm a huge comics fan. I think it'd last about five to ten minutes, but who wins depends on which comic the fight takes place in. The heroes always win on home turf.

Side note: The Power Ponies aren't really directly correlated to any super team. If you just match them to best equivalent, then:
Saddle Rager = Hulk
Miss Marevellous = Batgirl/Wonderwoman blend
Zapp = Storm
Radiance = Green Lantern
Fillisecond = Quicksilver/Flash/ any super-speed character
Masked Matterhorn = Doctor Strange

4052347 Long enough for Marvel and Hasbro to make a ton of money.

4052347 it be a tie, well counting Fluttershy out, only way to get her mad is for you to kill or wound an anamal. if shy gets mad it prob be a tie.

4052424 I wouldn't put to much faith in the home field advantage, even with cartoon logic, rainbow power, chaos magic, alicorn magic, and any other power they can draw from they wouldn't have a chance a even scratching Hulk or Thor.

4052467 We're talking comic book avengers, hulked out fluttershy wouldn't stand a snowflakes chance in hell.

4052482
If Discord is involved, the Avengers are in trouble. Discord's power is basically the same as the Infinity Gauntlet, and they only beat Thanos when he had the Gauntlet because Thanos had insecurity issues and Cap gave him a talking-to so fierce it would make a drill sergeant blush.

Additionally: None of the Avengers are unstoppable. Direct combat with the Hulk would fail spectacularly and hilariously, I concede that without hesitation. But remember, if they were unbeatable, the comic would've died off from boring the readers. Any interesting character will have at least some chance of losing. After all, Doctor Strange has tossed the Hulk around with magic before. He didn't win outright, but teleporting the opponent to another world is a pretty solid draw.

My point is, the Avengers still have the advantage, but not an overwhelming one. They'd probably win, but it wouldn't be a pushover battle.

*Final little rant: Don't ever doubt the home field advantage. If the hero doesn't win on his home turf, it's just setting up for a more satisfying victory next issue. I could go through my comics and show you about a dozen examples.

Well, that's a good question that deserves a better follow-up: are the Power Ponies involved here the actual Power Ponies themselves as seen in the 2014 Annual comic, or the Mane 6 in the roles of the Power Ponies as seen in the "Power Ponies" episode?

As for the match-ups regardless of the above:
Hulk vs. Saddle Rager — Everyone else seems to have sufficiently proven that this is unarguably debatable.
Marevelous vs. 'Murica — Hmm...a mind-controlled lasso, vs. "seeing faster"? If Marevelous can lasso Cap's shield away from him, she miiiiiiiiight stand a chance.
Zapp vs. Thor — The power of weather vs. the power of Asgard. One of those two has a capital letter.
I don't know Scarlett Witch, so I can't comment on this.
I only know a Quicksilver from a few scenes of X-Men DoFP, so if it's that guy, then he might win. Filli Second is just super fast, but that Quicksilver seems to be able to slow his perception of time down while moving super fast.
Iron Man vs. Matter-Horn — And lastly, "Freeze Ra—!" "Taaaank missile."

4052347
And then Deadpool pops out of nowhere and says "hey after we're done beating up this ponies do you guys wanna go to Taco Johns and get a couple of chimichangas? I'm buying!"

4052347 You forgot Hum Drum and Hawkeye.

4052347 well, actually Miss Marevelous is Wonder Woman, Radiance is Green Lantern, and Filli-Second is Flash

Your premise runs into the same problem as the Star Destroyer/Enterprise fight; that being, while one side has been sufficiently quantified that you can easily measure its capabilities, the other has not. You don't know the extent of the Power Ponies' abilities, or just how powerful they really are. We have a single episode for them, whereas the Avengers have over 30 years of comics, cartoons, and movies to draw from. tl;dr the Avengers are well defined, the Power Ponies are not.

With the power ponies current showings?

Just send Iron Man. He'd curbstomp them all pretty easily. I doubt the PPs will get more feats of much more development, making this fight super one sided.

4052511 What about Hum Drum dude? Hum Drum is a mmember of the Power Ponies as much as Zapp or Saddle Rager in the MLP comics Hum Drum was the leader of them when they lost their powers and if not for him they wouldn't even be friends so Hum Drum is an important member of the Power Ponies.