I just purchased the new 16" Macbook Pro with the M1 Max Chip and it comes to find that you cannot export an Alpha Channel black video out of Premiere nor out of Maccaption (a subtitling software). I am able to do so on my 2019 Macbook pro Intel. Has anyone had luck exporting an alpha black video? Please let me know what you have done to get this to work. I called Adobe, apple and Telestream and all are clueless.
I too have discovered this strange issue with alpha channel in video. First discovered it while using FCPX. It turns out that any video clip I playback that uses an alpha channel turns transparent to black. I'm surprised more people haven't run into this.