I know Smash now represents a pretty broad spectrum of the Japanese gaming industry (and is starting to branch out into Western characters, albeit somewhat tentatively, with Mii fighter skins like Doomguy and Vault Boy). Are there any video game characters not now represented that you would want to see, especially now that we're heading into the Switch 2 era?

My most wanted Smash character, by far, is Scorpion.

For one, it would probably be the closest we'd come to Street Fighter vs. Mortal Kombat, a dream matchup for 90s kids in the U.S.

For another, Scorpion could be worked into the game in a way that wouldn't be too violent for Nintendo. He wouldn't be the first character from a M-rated franchise to show up in Smash (Solid Snake and Bayonetta are two that come to mind). His FS could be him dragging someone off to Hell, and his harpoon would work great in the game.

Off the top of my head, Dante, Ryu Hayabusa, Kazuma Kiryu, Joe Musashi, and Amaterasu from Okami would be really cool to see in Smash!

So he can finally face Bayonetta. Only a moron would call her a slut. Anyway the matchup fans of both series have wanted for 15 years.

Smash needs a hero and he is the last hero around. Some people fuck at funerals. Let him smash in smash.

I will second Scorpion, since I have played Mortal Kombat games in the past year and counting and enjoy them.

Also...
Waluigi
Chibi-Robo
Noah and Mio

For some reason, I can't think of many characters I want. Smash is so full of characters and I'd rather some veterans be tweaked significantly than adding more than 10 newcomers to the next Smash.

I want them to diversify a lot more characters that feel repeated or else, cut them.
For instance, I want a Majoras mask young link that can change masks and transform into a deku, goron and zora.

I can even see the moveset:
instead of boomerang, bombchu, instead of bomb, change mask
deku: up B flower launch, b bubble, front b seed throw
goron: up b ground pound, b: roullout, front b: triple punch
Zora: up b: backflip kick, b: energy, front b: flip boomerang
Final smash: Fiercy deity mask

Also these two. Nahobino from SMTV & Demi Fiend from SMTIII:Nocturne

Oatchi, some Paper Mario representation, Astro Bot, Louis (from Pikmin), Waluigi, Bokoblin/Octorock, Tulin, WW/BotW/TotK variants of Zelda and Ganondorf, Geno, DragXDrive wheelchair guy, literally anything.

This girl: