Mouthwashing is really good. It seems like it would be a good game to watch like that; I don't think you lose a ton from not directly being in control (in spite of some of the themes). I was going to say i hope you enjoy it, but it is probably not something most people will "enjoy", even if they like it.

Skinamarink is probably the movie that I personally find scariest. I've seen in twice, and something about if makes me feel like I'm a terrified child watching (in retrospect really shitty) ghost videos on youtube. It's also just genuinely really well made and has great cinematography and sound.

I love all of the Final Destination movies. They are so ridiculous and so much fun. I can't believe it took until the 2000s for them to make a movie with the main premise being that people keep getting rube goldberg-ed to death. I definitely recommend the others; they're all pretty fun (except for the fourth one). All the others you mentioned are also some of my favorites.

I finished the Pumpkinhead series, and there's not really a lot to say about those sequels. How much you like the second one is entirely dependent on how much you like movies from that weird era after the 80s but before scream. I liked it well enough, but not super noteworthy. The other two sequels were made for TV sci-fi channel movies, and any negative thing you might assume based on that is probably correct. I also saw the new The Long Walk movie, and it was great. Very stressful, but also really emotional. You genuinely feel the bond between the characters, largely due to everyone giving a really great performance. The main two characters were especially good, I'm definitely going to be looking for whatever David Johnson is in next.