Video of under age kids engage in sexual activity is not child porn? Wow, there are probably a lot of people who wish you were on their jury.
Both are “children”, per se. So, kinda hard to imply an “adult” was exploiting them. That is the point.
Far as I can tell, they both did it consensually, so hard to classify it as “porn”, as if it was exploitation.
That’s all. I certainly am disgusted by any immoral behavior as they clearly performed, but if using common sense, I’d say it’s not “child porn” when they are both minors in the legal sense.