I've found a few just through a Google search, but unfortunately, there seems to be none that are active. The subreddit is super active, but I refuse to use that for multiple reasons. There are also the fandom wiki forums, but I've never actually looked into it.
It sucks because I too am obsessed with the franchise, but there's nowhere to talk about it besides Youtube, Reddit, and Steam. You'd think with how popular it is, there would be active forums springing up everywhere, but it seems people are sticking to already hosted sites instead of making their own.