So , given the actual situation , under the assumption that the first DLC is a SE rep because of Vergeben , Geno seem the most likely.
That's something that DQ/Sora supporters should understand , or even other fanbase as a whole. All speculation right now isn't "There could be a SE rep so who it is ?" for Geno.
Because if it was just a SE rep down the Line , I could see a DQ rep coming because a main DQ game could come the Switch. Or even Sora , if they somehow do a pocket edition of KH3 despise what the KH3 dev Team said.
And they don't have an "iconic" stature. (Neither does Geno.) Dragon quest is very old and huge in Japan , but lack world-wide appeal. If you're an icon , you're pretty much knowed everywhere. That's not DQ case , and other than slime , it lack the "Mr./Ms. Dragon quest." character.
Sora beeing iconic would be making him as important as , let's Say , Sonic the Hedgehog or Cloud Strife.
Characters that symbolise a franchise that had a Big impact on gaming (and by that , I mean BIG IMPACT. Gameplay elements that are used even to this day.), are old enough and are still an on-going franchise/or had a Good life , and are characters that even people who don't play video games should somewhat recognize are iconic.
Even Cloud is still "Mr.Final Fantasy Guy" for them.
And Sonic is the old rival of Mario , one of the oldest plateforming mascotts , still has new games to this day , he's iconic for that + he's well knowed even with people who don't play video games.
DQ is multi-platforms , and Sora main games are on PS2/3/4 , even his Nintendo exclusive were remastered for Sony consoles.
Geno , DQ , and Sora aren't iconic characters.
DQ and Sora aren't so close to Nintendo that they are Nintendo franchises/characters , like Banjo-Kazooie or Sonic was , at a time.
However , Geno is a Mario character. He's not the BIGGEST MARIO CHARACTER OF ALL-TIME , no , let's not be ridiculous.
Geno character symbolyse SMRPG , and how well Mario work as a RPG.
He symbolyse this , the creation of Mario RPGs (SMRPG , M&L , PM).
Even if it isn't their biggest franchises , the Mario RPGs are still kicking to this day , and are pretty old as well.
They are also not represented by a character in Smash , they only had 2 music tracks back in Sm4sh , and in Ultimate , some Spirits.
Simply speaking , Geno is the perfect candidate to represent the Mario RPGs. And that's not counting the huge following he has since Brawl , Sakurai and Nintendo know the requests.
He fit in in Smash , design wise , and history wise.
Given the current situation , and the first DLC beeing a SE rep , Geno has way more going for him than his candidates.
There , I know his chances have been talked about to death , but I think this point of view wasn't talked about a lot.