This is according to leakster Dusk Golem who claims that Resident Evil 8 will be arriving in 2021. VGC has also since verified these claims with their sources, suggesting that there could be some truth to them. Dusk Golem also revealed some additional details about the game, where it will feature “huge changes” and how it was apparently not designed to be a “main” Resident Evil title.
Okay, so the little game is done. This will be breaking this month with more details later not by myself, but I've needed to clear some stuff up. "Resident Evil 2021" is Resident Evil 8, but it wasn't always RE8. During most of its development it existed as Revelations 3.
— AestheticGamer aka Dusk Golem (@AestheticGamer1) April 4, 2020
According to Dusk Golem, Resident Evil 8 had started out internally as Resident Evil: Revelations 3. However, during the testing phase, the game was so well-received that Capcom decided to make it a main title and rebrand it to Resident Evil 8. We had previously heard (also from Dusk Golem) that Capcom had initially scrapped the version of Resident Evil 8 that they were working on and rebooted the project in 2019, which presumably based on his tweet, is based off on Revelations 3.
Other details about the game also include how it will be sticking to its first-person perspective, something that we had also previously heard. In any case, with a rumored 2021 launch, we could be in for a wait before more details about the game are revealed.