- Gamefreak officially consecutively stated in the media conference that it is a main core series game. The 2019 game is as well.

- Gamefreak have targeted this towards newer / casual fans.

- Gamefreak officially stated that core games will come in two supplements for the future, Games like this for the newer crowd and your typical Pokémon game for hardcore fans. The 2019 release is geared for hardcore fans. This is targeted to introduce new players into the franchise adopting some familiarity with the ever successful Pokémon Go.

- The 2019 game won’t have casualisation because of this game.

- Pokémon Go isn’t required to play

- The Accessory isn’t required to play.

- Gamefreak and Serebii have given official confirmation that the games have online activity. Their was a mistranslation earlier in the stream which caused hysteria among fans.

- Pokémon can use 4 attacks just like in the main core games rather than Pokémon Go’s. The attack system mirrors the main core games.

- Pokémon Attacks have the standard animations from the main core games as we see with hyper beam, Swift, seismic toss and the like. They do not function like Pokémon go. The animations are crisper and cleaner.

- Wild Pokemon have levels that mirror the original wild Pokémon from Kanto, we see this with the mt moon clefairy being the same level as the original gen 1 games and the other overworld Pokémon matching the rest of the wild Pokémon of mt moon.

- Wild Pokemon have both levels and Cp. The Cp likely is a modifier from transfer and for familiarity since the game is targeted for that audience in mind.

- Wild Pokemon are caught like in go.

- The accessory makes it easier to catch Pokémon

- Standard core series items can be used in the wild before throwing a ball to increase or decrease capture.

- Items can be used in battles.

- Double Battles are back

- Players can co op with other players at any time freely

- Co Oped players can participate in story mode battles and help you battle in double battles. You can do the entire adventure together or separate. Perfect for couples and siblings. (Multiple save files confirmed?)

- Co Oped players can help to catch Pokémon, both getting the spoils.

- The game features Pokémon centres.

- Wild Pokemon appears in the overworld like standard JRPG games meaning you can catch what you want, no more spending hours trying to get that elusive Clefairy, meaning you can enjoy the action more.

- The story mode features Team Rocket, they use some new Pokémon they didn’t use previously giving variety to their typical rosters

- Mewtwo plays a part in the story unlike in the originals

- The new device is an OPTIONAL seperate tool much the pokewalker. It’s not needed to play the game, but rewards you like the pokewalker allowing you to take your partner Pokémon for walks and getting rewards.

- You can trade Pokémon between Pokémon Go and the Switch at will and mix and match at your desire

- Transferred Pokémon go to a Pokémon pal park clone, exactly the same as gen 4.

- All pokemon follow you like in HGSS

- Pokémon Amie clone returns

- You can dress up and stylise your pikachu and eevee as you want without restrictions

- The story Pikachu and Eevee cannot evolve exactly like Pokémon Yellow. Others however can

- The standard Pokédex Returns, no more rotom lol

- As revealed by Gamefreak and Serebii, a brand new Pokémon is being offered for players as an exclusive.

(Source: https://www.reddit.com/r/pokemon/comments/8njieu/a_facebook_post_from_pokemon_exclusives_has_a_big/ )