https://retronauts.com/article/906/embarking-on-a-strange-journey-redux
Much more on the link, lots of cool stuff including the inspirations for SJ itself, and additions in Redux, etc.
To be exact, it was developed as a spinoff from the start. The promotional staff at the time judged the game to have high enough quality to be marketed as a numbered title, so they suggested selling it as a numbered SMT game. Even Mr. Kazuma Kaneko, who worked with us to design the human and demon characters and pen the original story, backed up the suggestion, saying it was "good enough to be called Shin Megami Tensei IV."
But, because it was conceived as a spinoff, we enjoyed the freedom of going off on a tangent from the mainline games (and the extra pain and suffering from that, haha). Therefore, I felt a strong resistance to market it as a numbered title, and I ultimately rejected the suggestion. I think I would be a little more flexible about it now, but my past self who had just experienced the pain of creating a new title wasn't as confident, and I couldn't make that decision then.
We would like to consider a sequel, and we actually have ideas for the story and a new game experience. Whether we can make it happen, though, depends on how well this game performs.
I loved Alex Garland's previous film Ex Machina, so I was also looking forward to Annihilation.
[...]
By the way, Maaya Sakamoto, the voice actor of Zelenin in Strange Journey Redux, was the Japanese dub actress for Natalie Portman in Annihilation. In that sense too, I feel a strong affinity with the movie. She is the exclusive dub actress for Natalie Portman in Japan, and also the Japanese voice of Aigis in our Persona series. I especially love her dub work for Fiona in the TV drama Shameless!
Although Ms. Sakamoto plays many characters, to think she's the voice of both Aigis and Fiona... it's just incredible!
Much more on the link, lots of cool stuff including the inspirations for SJ itself, and additions in Redux, etc.