It works for any tradable piece of gear (BoEs, loot from dungeon that can be traded to other members for 2 hours, etc) and any enchant that the high level can do. Though the enchant may have a hidden requirement (level 25, engineering 250, LW 450, tailoring 500, etc) that prevents you from using it.
So you'll see players with leggings of the fang with spellthread on it. Or dungeon shoulders (with verse) with a shoulder enchant. Frag belts (for those who didn't get northrend engineering). Venomstrike with a high level scope. Etc.
Yes this glitch is years old. AFAIK no one has been banned for it, but it is exploiting to get around in-game limitations, so its up to each player if the risk is worth it. Pretty sure they are banned for TC. I personally won't use it or put it in the quick start guide.