Transparency

So I am trying to export a video that I made in element 3-D on after effects. I am just learning the program and messing around. I am trying to export this with a transparent background, but when I do so inside Premier Pro or OBS studios the black background reappears. I’ve rendered it with QuickTime eight bit plus Alpha channel. It still appears. I’ve used the Adobe media encoder and made it a web file to include Alpha channel and black background still appears please see videos for reference.. I am getting really hung up and defeated and appreciate any help