Back in March, we relayed word of a report about a new Persona spin-off game starring Goro Akechi, a prominent character in Persona 5 and Persona 5 Royal. The report was shared by Zippo, a well-known industry insider and leaker who has proven reliable in the past, particularly with Persona. For example, they accurately leaked the Persona 4 Arena Ultimax remaster and all of the recent Persona 5 ports. That said, they recently doubled down on the aforementioned Akechi game report.
The update is very brief, but Zippo reiterates the game "is real," and notes that "hopefully it's something they [Atlus and Sega] announce before too long." It's unclear if Zippo is under the impression the game will be revealed soon or if the latter part is just wishful thinking. Whatever the case, for all wondering if the Akechi game was still happening, it apparently is.
At the time of the initial report, Zippo described the game as a spin-off and not an RPG. Adding to this, it's claimed that the game will focus "on his adventures and skills as a star detective." When the game will release and what platforms it will be available on, weren't mentioned in the initial report and this hasn't changed.
As for Goro Akechi, he is known as the second coming of the detective prince. In other words, he's the Persona 5 version of Persona 4's Naoto Shirogane. In Persona 5 and Persona 5 Royal, Akechi is investigating the Phantom Thieves of Hearts. Again, he's a prominent character, but not one you would expect to be the protagonist of a spin-off game.
All of that said, take everything here with a grain of salt. While Zippo proves increasingly reliable when it comes to Persona, in particular, it doesn't change the fact that everything here is unofficial. Further, even if everything here is accurate, it doesn't mean it will remain so as everything is subject to change. In fact, there's no guarantee that even if this project is real it will ever see the light of day. As for the implicated parties -- Sega and Atlus -- neither have commented on this new update or the previous report. If this changes, we will be sure to update the story with whatever is provided.