A tweet from the official Pokemon Twitter account heavily implies that news regarding Pokemon Diamond and Pokemon Pearl remakes is coming very soon after fan disappointment that nothing was announced at the most recent Nintendo Direct.
Rumors around an upcoming remake of Pokemon's 4th generation, Diamond and Pearl, started circulating wildly last year. However, because the Pokemon franchise has remade each preceding generations in the form of FireRed and LeafGreen, HeartGold and SoulSilver, and most recently Alpha Sapphire and Omega Ruby, it's assumed that Pokemon would continue the trend with Diamond and Pearl remakes. But the lack of news at the most recent Nintendo Direct worried some fans, but it looks like The Pokemon Company has plans to make announcements on Pokemon's 25th birthday.
Earlier today, the official Pokemon Twitter announced that "Turtwig, Chimchar and Piplup are preparing for #Pokemon Day." These three Pokemon are the starter Pokemon for Diamond and Pearl, which veteran fans are certainly already aware of. But the Pokemon Twitter account also specifically calls out the Sinnoh region in the tweet. This heavily indicates that news regarding Diamond and Pearl remakes are coming on Pokemon's 25th anniversary on February 27. However, it's possible that these remakes are coming in a way fans weren't anticipating.
Looking at the tweet's specific wording, "Let's go, Sinnoh!" It's possible that this is a hint that the Diamond and Pearl remakes will be in the same style as the Let's Go, Pikachu! And Let's Go, Eevee! Games. While the Let's Go duo was well-received by critics, it changes up the normal Pokemon gameplay quite a bit from the traditional style. Players still battle other Pokemon Trainers and Gym Leaders, but when facing wild Pokemon, players pacify them to catch them rather than widdling down their health.
Based on Twitter's reaction, most players don't seem excited about this possible change-up. Most Pokefans have been expecting Diamond and Pearl remakes in the familiar, traditional format that Pokemon was founded upon. Inspired by the mobile spin-off Pokemon GO, the Let's Go games are great for kids or anyone new to the franchise, so if speculation is correct that Diamond and Pearl will be the next Let's Go pair, it would be disappointing to many older and veteran fans out there.
Online personality Shinobi602 was one of the many who voiced his dismay for a hint in the Let's Go direction. Other Pokemon fans are threatening to "quit Pokemon" if this is true, saying that it'll likely ruin the fourth generation. However, official news will have to wait until February 27.
Pokemon Diamond and Pokemon Pearl remakes are rumored to be in development for the Switch.