@Prince Areo  
Luna as Meta Knight maybe?

Princess Celestia’s main in Smash is probably Roy.

To anyone who has to ask: You can have up to 8 controllers connected to the Switch at once.  
Super Smash Bros Ultimate has something called 8 player Smash.  
There might also be other games that can be played with more than 4 players.

@Azerdoe  
I understand, I’m more of a casual brony myself.

@Beau Skunky  
No no, I’m saying I enjoy the ponies. I just don’t consider myself a fan anymore, if that makes sense.

@Azerdoe  
Still Pony content. :)

@Beau Skunky  
Not really a fan, just like the content produced by fans :)

@Azerdoe  
Ok, to each their own.  
^{A bit funny for an MLP fan to call something “childish” though, no offense. Even “childish” things can be fun.}

@Beau Skunky  
To be perfectly honest and I mean no offence, I really don’t care. I’m not a fan of Smash as a whole and find it childish. I was just saying that I don’t see Twilight being Robin, that’s all.

@Azerdoe  
Zelda might suit her too. Though, honestly female Robin makes sense, because of the book/magic thing.
 
Here’s a toughy, who would Derpy/Muffins “main?”  
||For me, I’d say Luigi, because like him, she’s usually in another character’s shadow, but is still quite popular regardless, like him. ||

@Beau Skunky  
Does it matter? But if pressed, Twi could be Ness or one of the princesses.

@Azerdoe  
Who is your choice for Twilight’s main then? (Also, just ‘cause you’re not into a series, doesn’t mean you can’t enjoy a SSB character. The SSB series introduced me to many games I never tried before.)
 
Alternatively, Isabelle could suit Pinkie Pie, (party poppers, and goofy weapons) or Fluttershy. (being a cute/shy yellow animal)

@Gay Space Raptor  
I don’t like Fire Emblem, hence why I said it’s not my first choice.

@Azerdoe  
Twi as Robin totally fits tho lol. Robin is the main tactician and strategist for the army in Fire Emblem Awakening, and I feel Twi would totally dig being in that role. Not only that, but Robin has a similar power of friendship thing going on like Twilight does lol. Robin is also a magic user as well. Though I’m curious to know who was your first pick for Twi
 
I agree though that Kirby feels more fitting for Pinkie instead of Jigglypuff

Choices obviously not based on their personality or Fluttershy would be Lucas. But it would also make sense if she picks Pichu. The smirk definitely means she is winning though considering how good Pikachu is.  
Rarity would probably be Bayonetta.

Their mains make so much sense. I especially love Spike as Ridley.
 
Can you have that many Switch controllers connected to one Switch? Shouldn’t they each just have a single Joycon?
 
@Background Pony #2A38  

 
That actually makes sense. lol  
Though, she’d probably be costume-swap Alex.

I’m so torn right now on if I want Rainbow Dash or Fluttershy to win. Rainbow Dash(who’s my favorite of the Mane 6 and in MLP) is playing as Sonic, who’s one of my favorite characters. But Fluttershy’s playing as Pikachu(not only my favorite Pokémon, but my overall favorite)…… unless they’re somehow playing teams and Dash and Shy are paired together, then in that case: GO FLUTTERDASH!!!!!

Rarity should play as Steve. She has a thing for gems or anything shiny right?

Love Fluttershys smirk there. Plus interesting choices for them. RD being Sonic is obvious, Pinkie being Jiggilypuff is strange as I’d figure Kirby would be her pick. Twily as Robin is not my first choice but okay. AJ as Banjo is just sad cause it’s like a stereotypical choice, but eh. Spike as Ridley is both funny and accurate cause he’s living that power fantasy.
 
Good picture overall 👌

Just wait until Steve shows up, unless there’s another character you’d like to play as…