So when does it do it? Under light throttle? I finally listened to the video.
It sounds like a resonance to me.
I know someone said they checked the exhaust hanger(s) But did you actually jack the car up, crawl under it and look at the rubber exhaust hanger ahead of the rh rear wheel. The rubber part wears out where it mounts on the peg that's welded to the car. You can't tell it's trashed by just looking at it. You gotta actually lift the exhaust up and down, if the rubber isn't tight on the peg then it'll cause the car to rattle and vibrate at a certain rpm. And it only seems to do it while driving, not while revving in neutral.
Sounds stupid, but I've seen it happen on almost every 2017+ Mirage.
Could be one of the heat shields on one of the cats.
Can you get it to make the noise while in neutral? Does it vibrate the car at all or just make a noise?