Opposed leak from reddit user "Verdeckt":
To start off I used to work at Sora until I got terminated back in late 2017 for circumstances I can’t discuss. I’ve decided to share some info regarding the new title with my sources being myself and others I’ve worked with whose names are staying withheld. To start off NO one knows who is actually in the game in the company until given notice. I’ve been lucky enough to have sources from actual people working on the characters and sources to support this. In decision to share this is because there is 5 months are left and why not. I’ve seen so many leaks going around and it’s hard for anybody to take anything seriously so sharing this and whether or not you believe it is all up to you. What I have to offer is insight on Newcomers, Stages, and Modes and will be posting one category at a time.
NEWCOMERS:
*Inkling, Daisy, and Ridley were already revealed at E3. As for newcomers there will be only 7 more to appear. (10 total)
CHORUS KIDS Will be playable and finally realized as a character after being scrapped in Smash WiiU/3DS. Their mechanic as a character was similar to the Ice Climbers and were decided to be implemented in the next title. They are a trio character and their movement relies on the rhythm in which the player presses the button on the controller in sync with the characters movement and attacks. The better you are in rhythm with the character determines the amount of damage you deal in attacks. Their Final Smash has their conductor come down and direct the choir playing a short verse of "Dreams if Our Generation" (from Rhythm Heaven Fever Wii) ending with a reckless scream as they do in the DS title of Rhythm Heaven.
HEIHACHI The grand master of martial arts appears in Smash. Heihachi from the Tekken series is added to the fray and was part of the top realizable characters from the ballot. He was considered early on in development working with Bandai Namco and such. His moveset is difficult almost like Ryus where the direction of his attacks revolves around the players direction of the control stick. What differentiates the two is his moves from Axe Kicks to Cresent Kicks along with short and long jabs. He will have both his young alt. from Tekken 3 and old alt. from Tekken 7. His final smash will have him glow in electricity and perform a devistating combo causing your opponent to explode on spot.
*CHARCTER FROM XENOBLADE SERIES: The legendary Aegis driver Rex is the pick here and for a short time competed with Elma and Cross. With Xenoblade X and Xenoblade 2 in development during the same time it came down to who seemed the most intriguing in what they had to offer. Cross was quickly scrapped as an idea due to the games avatar not really bringing nothing unique to the table though he will appear as a trophy. Next was Elma was close due to her potential in utilizing the mechs, but in the end took the place as an assist trophy in favor of Rex being able to represent the new Xenoblade 2, a direct sequel that would be released on the Switch. His moveset uses his arts similar to Shulk but his aegis sword switches between Pyra and Mythra. His movement and attacks are based off his game from Anchor Shot and Double Spinning Edge etc. Dromarch and Tora will be featured in his Final Smash and perform in similar manner to Shulks Final Smash Chain Attack.
SIMON BELMONT Was a popular vote in the smash ballot (out of realizable characters he was consideted top 20). One of the last of big icons in gaming, Simon will utilize his whip as his neutral attack similar to Mega Man using his Mega Buster as his neutral attacks. He will use his classic design from the original Castlevania as well as his look from Super Castlevania IV. His Final smash will feature him using his Cross to stun all the opponents in his field of vision and then proceeds to hit his opponents with a devastating whip lash. Gray Fox from the Metal Gear series will also reappear as an assist trophy.
*POKÉMON FROM SUN/MOON Decidueye was picked to represent the new generation where he features a moves from the game like Leaf Blade, Spirit Shackle and his Final Smash being his Z Move Sinister Arrow. He was chosen out the game Pokemon Sun and Moon titles through his design and his Sakurais faith in the characters moveset potential. Other ideas were Alola Raichu (who’s now a Pokéball item), Incineroar (Was quickly dismissed after consideration), Mimikyu (to what believe was going to have few assets from Pikachu but NOT aimed to be an echo fighter), and Lycanroc (Where the idea was for his Final Smash have him transform into his Night form and use his version of Lycanium Z).
*ARMS CHARACTER: Was one of the debatable characters on whether he should even be included in Smash due to him being a newly fresh IP. But the character Springman made it through the process as the character seemed he had a lot to offer from ranged attacks and a unique design that if wasn’t included in this iteration of smash, may never be able to be realized. His move-set revolves around his different sets of abilities from Toaster, Boomerang, and Tri-bolt. His Final smash will be a barrage of fists thrown at his opponents similar to DK and Giga Mac, though Springman’s range to trigger his Final smash has more range.
RAYMAN The last character here, amd was popular in the Ballot from Western audiences, he's finally chosen to be playable. With Nintendo and Ubisofts recent relationship and cooperation it helped make the process easier. His move set will heavily resemble Rayman Legends as well reference some of his games from the past. His color swaps will include Rayblox, Raymesis etc. In his Final smash Rayman will rise the Mosquito and gives the player the ablility to shoot at their opponents from the background. Globox, Barbara, and the Teensies will appear as trophies. The Rabbids will appear as Assist trophy.
(Source tells me previous DLC Mii Costumes from Waves 1 through 6 will return along with new unique ones that are unlockable in game with some based off popular votes from the ballot).
STAGES:
Returning Stages: Peach's Castle (64), Delfino Plaza, Mario Bros., Rainbow Road, Paper Mario, Kongo Jungle (64), Jungle Hijinxs, Pirate Ship, Brinstar Depths, Pyroshpere, Yoshis Island (Melee), Wooly World, Fountain of Dreams, Orbital Gate Assault, Mute City (Melee), Gamer
New Stages: Aquarosa (Starfox Zero), City Trial (Kirby Air Ride), Hoshido (Fire Emblem Fates), Rhythm Heaven (Rhythm Heaven Series), Mishima Dojo (Tekken Series), Mor Adain (Xenoblade Chronicles 2), Dracula’s Castle (Castlevania Series), Melemele Island (Pokémon Sun/Moon), Spring Stadium (ARMS), Glade of Dreams (Rayman Legends)
*Stages will be categorized by Normal stages which surprisingly will fit all 110 stages on screen, and Custom stages where “Stage Builder” will Return and have have both elements from Smash Bros. Brawl and Wii U in order to allow players to create both structured stages and creative stages to their liking.
MODES:
Classic Mode: (Based on the 3DS Version but revamped, Race to Finish, Trophy Rush, and Target Smash will be featured in this mode.)
Adventure Mode: (Returns from Melee but due to the huge roster the mode will only feature areas and stages from the original Smash 64 roster Ex: Mushroom Kingdom, DK Jungle, Hyrule Temple etc. As you continue to unlock characters more variety will be added to your adventure mode experience Ex: Unlocking characters like Meta Knight, Falco and Greninja will add them within the mode to be fought within their respective franchise.)
All-Star Mode: (Unlike Smash for WiiU/3DS this Mode must be unlocked once again just like Smash Bros. Melee/Brawl. Stages will still go by year of relevance as well.)
Event Match: (Will function just as in Smash WiiU and this time around it will help streamline the idea of unlocking other characters like in the past. Setting the difficulty is still there so you can manage your event match experience.)
Target Smash: (Functions just like it did in Smash Bros. Brawl bringing Levels back and featuring multiplayer as well.)
Target Blast: (Returning from Smash Bros. WiiU/3DS)
Home Run Contest: (The mode has a different background but as far as that it functions the same)
Multi-Man Smash: (The Miis are still the Enemies and fictions the same as in the other installments)
Smash Run: (The whole area from the 3DS Version Returns as well as a few new areas as well. This mode being in the Switch will allow you to play both Local and Online Multiplayer. (Enemies from a hidden character’s franchise will not appear until unlocked within the game.)
Smash Tour: (Revamped and better than the previous installment stay tuned)
Tournament Mode: (Now available both Local and Online)
Smash Royale: (The new mode that features the player from choosing a number of different characters to a max of 5 and battling it out. The stock icons of each Fighter you have chosen will be featured under your damage percentage and will be up to only 4 players. (Will also be an online mode)