Greatsword of Sin'Dorei doesn't work as transmog

[vinkkk]

WoW Freakz item link: https://www.wow-freakz.com/item_finder.php?item=45205&name=greatsword-of-the-sin-dorei
Bug description: I equipped the sword, and because it is epic it should be able to apply it as a transmog. But it is not appearing in the collection when it is equipped. I will mention that I used vote points to take it on my human character, I know it is only obtainable by horde.
Proof: https://ibb.co/jVNdaK

[Xtravagant]

According to WoWhead, the sword should convert into Claymore of the Prophet on your Alliance character. See if you have that in your appearance tab.
Edit: Technically, you shouldn't be able to transmog Horde-only Swords as Alliance, and I don't believe you can loop around that by voting.