From what I’ve read there’s little to none surviving accounts as to what their actual rituals were. Any ritual performed now would be 99% fiction. So yes cos-play or dress up done by grown children.
When I left home for college in ‘68, there were students who were into the cosplay and make-believe, too-they claimed to be into paganism, Eastern religion or a mix of both, but they didn’t seem to really know much about any of it other than to dress up in what they thought pagans had worn, get drunk and/or stoned, get naked, dance around fires in the woods, have sex, etc-even as a clueless country girl, it looked like dress up and make believe to me-this Iceland thing sounds pretty much the same...