Might as well ask: Does Collette sound like Ocean Vegeta in the restored soundbites or not? XD

@donut64s  
Actually, that makes sense.

@Background Pony #9020  
The closest the Mane 6 get to circular eyes is slanted ovals, whereas the breezies that have been theorized to be male have eyes much closer to true circles.

Eye theory makes no sense. When the Mane 6 transform they have round and almond shaped eyes.

Actually, I follow antennae theory.
 
White antennae color = male

Maybe Breezies are like the Dwarves in Discworld and you just can’t tell if one is male or female because they all look the same.

Eye theory is the most garanteed. Circular eyes - boy; almond-shaped eyes - girl

@Beatfox  
OOPS.
 
I derped and switched around which eye shape was male and which female.

@ze  
@Draco_2k  
@OkieDokieLokie
 
Someone already made a pitch-lowered video here.
 
Also, as Telaros pointed out in the comments here, the eye shape theory does still hold water. Seabreeze (along with the other suspected-male breezies) has near-circular eyes, whereas the closest the Mane 6 come is a slanted oval shape.

Actually, hair LENGTH might be an indication.
 
The manes of the mane 6 seem to be longer and flow in the wind more.

@Minus  

 
I don’t see anything in the transcript that suggests that, but if this is true then what you say would make sense.
 
Also, according to this Tweet, the one in the mushroom hat is named Breezette. We might want to check the credits.

@ze  
Woah, interesting. I should. I can’t really do that though, as my computer’s sound doesn’t work right and I have no time to fix it. Maybe somebody else? :P

@ze  
Dude.
 
Hm. Pitchshifting might be a good bet, good idea.

I think in order to tackle this problem, we need to first define what assets we are working with.
 
If memory serves me right, there are at least 8 Breezies whose genders are known. The unfortunate problem is that only one of them is definitely male, Seabreeze:  

 
As for females, we have 7 to work with. If we assume Breezies follow the usual male-female set up, we can deduce that his wife is female:  

 
Lastly, if we assume that all the transformation spell that Twilight cast did was change races, we can deduce that their Breezie forms reflect their pony genders:  
 
 
These were the best images I could find on DB. I’m too lazy to take my own right now.  
_{^{(Note: We are just going to say that the mane 6 are female. Fyay your crazy headcanons.)}}
 
From here, we can figure out genders. The main problem is that we have a very limited pool of males to use for comparison (1).
 
The eye theory falls flat as Rarity clearly has the “male” eyeshape (NO. NO. WE ARE NOT GOING TO EVEN SUGGEST THAT SHE’S MALE. EVEN THOUGH SHE WEARS FALSE EYELASHES… Wait… … NO. GO BACK UP AND READ WHAT I SAID. Fyay YOUR CRAZY HEADCANONS!)
 
Straight hair vs curly doesn’t work as the mane 6 have both straight and curly hair.
 
As far as we can tell, the antenna theory does seem to work. The mane 6 has the same color antennae as their bodies, signifying they are girls. Unfortunately, we don’t have enough data about males to confirm this.
 
There’s another theory that is based off the fact that Seabreeze has slightly thicker legs than his wife. This could work, but, again, we would need a bigger pool of males to work with to be sure.
 
 
There is one last thing we could try doing: sound editing.
 
Lower the pitch of the breezie mane 6 until it sounds normal, then use that as a baseline to modify other voices to see if they sound male or female. I would suggest checking Seabreeze first to see if this method would work.

I can’t see a difference between the eyes or antenna. But then I assumed the pollen they had was how they made babies, so they’re probably all the same sex.

@SRQ  
Only dudes and bros reproduce this way.

They reproduce by budding.

@Grieffon  
In this theory, mis match would usually equal male and matching with coat would be female

@cheezedoodle  
Welp.

They’re hermaphrodites.
 
Problem solved.

… I don’t see the difference between the antennas. Someone mind pointing it out?

Theory #3: They’re hermaphrodites. But I’m also going to go along with the “don’t really care” opinion first and foremost.

@Background Pony #5B85  
We’ve made timeless relics out of smaller things in this fandom.
 

@Draco_2k  
I have a feeling that I’ll continue to not give any fucks about the gender of 1-time-appearance creatures in a cartoon.

I have a feeling this will never be resolved.