Oh that's actually funnily enough the most applicable 2nd person mechanic.

I think it might be a result of a gamejam? I can't remember but i remember how unique that sound, but i can't find that one i saw though. I googled a bit and it seems a lot of indie dev attempt on this idea.

Screencheat on steam 4 players everyone’s invisible and the only way to see what’s happening is look at other players screen

Can't seems to find it now, but there's a lot of attempt on this idea though, so we might actually saw a different game. I remember seeing it in early or mid 2010s.

There is one better example of second person perspective than Mario 64, which I don't really agree with since the disembodied camera isn't a character's perspective per se. Unless it is. I don't really know the lore of Mario 64. So I shouldn't comment.

In one of the need for speeds you are pursued by the cops and then the camera goes from your normal racing game perspective into the cops perspective, but you're still driving your car, so you're seeing your car that moves around and responds to your controls from the cop who's chasing you's point of view. Pretty trippy.

I never played it myself, but I once watched a YouTube video about second-person games. And this was the example they used.