I added some on that I saw before I made this list just in case you hadn’t seen them and they end up interesting you. If you click on the titles they will take you to the JustWatch page that will tell you all the places that title is currently available to stream. (I took all the release years from IMDB and sometimes the JustWatch release years don’t match by a year or two, I don’t know why).
I tried breaking it up into four categories: Sci-Fi/Sci-Fi Horror, Other (psychological drama, etc.), Horror, and Don’t Recommend. They are in no particular order and I’ve been jumping around myself. The titles on the list span a scale from light, mildly mind-bending to mind-destroying fear of the unknown.
Dark City (1998) [Note: Do watch the Director’s Cut if you can find it, mute the narrated audio at the opening as it was added by the studio but completely spoils the mystery of it all]
I Trapped the Devil (2019) [Note: Slow pacing without much development, some well framed shots with good lighting but almost no substance, the highlight is the voice actor for the voice in the cage. It was recommended to me but is the only one on the list that I’ve both seen and didn’t have fun watching.]