You can though it’s a bit of a roundabout way of doing it.
P2P releases typically come from private trackers, so you’re having them go from private trackers --> usenet --> public/private torrents
Scene releases that leak to the public typically hit private trackers/usenet around the same time, so you’re having those go scene --> private trackers/usenet --> public/private torrents
In others words anything you’re seeing in usenet has already been uploaded to at least some private trackers & possibly public torrents.
Of course with public torrents anything goes, unfortunately with the demise of RARBG public torrent users are only seeing a fraction of scene/p2p releases. 1337x/TorrentGalaxy does cover some of this but they aren’t covering nearly as much as the RARBG uploaders used to. So IMO if you’re seeing a scene/p2p release that hasn’t already been uploaded at 1337x/TorrentGalaxy then sure go ahead & create the torrent from your usenet download.