I think we're gonna see a double reveal at E3. One of the two will be 'Legendary Trainer' from Legend's Arceus since they have a cross-generation assortment of starters. I also suspect that the other one will probably be a Bandai Namco rep.
Additionally I feel like Legendary Trainer would come with a Jibanyan Mii Costume (because Yokai are the Pokémon of Japanese of mythology) and possibly a Digimon Mii-Costume. The Mii costume would probably be Omnimon since while Agumon is the mascot Omnimon is both the Charizard and the Mewtwo of Digimon.
It does not make sense to me that we haven't had a Level 5 representation of any kind yet, a Jibanyan Mii-Costume coming with a new Pokémon rep would make a lot of sense.
I'm slightly less confident on the second Mii-Costume coming with Pokémon for two reasons. Firstly Digimon would be anti-thetical to the historical theme of Legends Arceus, and could easily come with a Bandai Namco rep like Lloyd or Yuri... secondly Digimon could actually be the second Bandai Namco rep since its actually had a weird amount of influence on gaming history while it was still in its infancy and just a V-Pet game without a console game (or anime) behind it.
Obviously there is a good argument for Lloyd/Yuri to get in; the fighters pass has definitely had a bias towards characters with a similar aesthetic design to them. BUT allow me to explain why I think there is a chance we'll see a Bandai rep rather than a second Namco one.
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When we were stuck on talk of the spectacular 3D graphics of
Mario 64 and racing games, we saw a huge hit in the form of [
Bandai's]
Tamagotchi — a tiny key chain boasting pictures made up of no more than 10 or 20 dots. At that time, I thought that
Mario 64 had lost to Tamagotchi. [laughs. Miyamoto quickly adds in English: "I'm serious."]
—Shigeru Miyamoto
[21]
As I'm sure folk are sick of hearing, but Digimon was an off-shoot of Tamagotchi; meaning this quote, and the larger context of it which arguably paints the Wii/DS era as being somewhat inspired by V-Pets, can also be held up as counting for it.
Nintendo actually had huge success with their own V-Pet brand in those days, Nintendogs. Unfortunately for understandable reasons they've decided it should be kept to an assist trophy. The issues that exist for Nintendogs and to a lesser degree for Mametchi or hypothetically for a Chao (and I've probably spent more time raising Chao than playing the rest of the Sonic Franchise so please forgive my wish for a V-Pet rep) is hon
Amusingly considering Nintendo had their eyes on that scene it was around this time frame, roughly one year after Digimon came out, that Pokémon Yellow came out. As you may remember it actually added basic V-Pet elements in the form of partner Pikachu. I have to wonder if Pokémon doing that played any part in Digimon deciding to expand into home console games, and later going multimedia.
Amusingly Pokémon Gold came out after that would also expand on the happiness system, and add eggs and babies which are also common V-Pet elements. In a weird way, effectively cementing Digimon as the Castlevania of two different genres.
... BUT there is every chance it will just be Lloyd or Yuri. Personally I'd like to call it a three way tie.