Out of left field, Nintendo revealed their first, (maybe second, if you count the plant), DLC character for Smash Ultimate at the Game Awards a few hours ago, and it's the protagonist from Persona 5, also known as Joker.
There were a few signs of this happening, such as Sakurai himself stating in an interview that he played and loved Persona 5, and even that a lot of the menus in Smash Ultimate were modelled after the incredibly stylish ones found in Atlus’ masterpiece of a JRPG.
So how exactly will Joker fight? Well we haven’t seen any actual gameplay of him yet, just the animated reveal trailer in the which the other members of the Phantom Thieves discuss their leader getting invited to Smash. Maybe that means they’ll be incorporated into his gameplay as well, such as an “All-Out-Attack” that features a random three members as his Final Smash? Joker will likely be a quick and nimble fighter, utilising his dagger and pistol, alongside his incredible agility, to dance and weave around opponents. Many of his Specials and Smash attacks will likely include him using his Persona’s power, and while in Persona 5 Joker can wield almost any Persona in the game, that would be a nightmare to programme for a fighting game. Logic dictates he would use Arsene, the first Persona he obtained, or perhaps even Satanael, his ultimate Persona that he unlocks at the end of the game, (uh, sorry, spoilers!).
Joker doesn’t yet have a release date, but based on what Sakurai has stated about DLC before now it stands to reason he would drop some time in early 2019.