Recently, Atlus’ Steam page suddenly added another new product. There are 13 Atlus titles on Steam and that number was recently updated to 14. This implies that a new Atlus game will be coming to Steam.
It is possible this could just end up being just a DLC for a game they have already released on Steam however it is still uncertain either way.
There have been hints that Shin Megami Tensei V may see a Steam release at some point as it was included in the Nvidia Leak of upcoming games, a lot of which is coming to PC. Data miners also found files in the game referring to PS4 and Windows.
Fans have also suggested that Persona 5 or even Persona 3 could also be a possibility given that Atlus is supposed to release new information for the series 25th Anniversary celebrations. Some have even suggested that it could be 13 Sentinals Aegis Rim as the game was recently announced to be coming to Switch.
It should be emphasized that this is still just a rumor and there has been no official confirmation from Atlus. Sega however has stated that they want to port more of Atlus’ games to PC so we may slowly see more of their games on their Steam page.