Admiral Taylor’s Greatsword
Has anyone heard anything on if this sword is going to be moggable in upcoming patch or not yet? I’m still hoping it will be, but I can’t play the PTR to find out.
Admiral Taylor’s Greatsword will be eligible for transmogrification in an upcoming 6.2 PTR build. To keep things fair, there will also be a Horde equivalent (in a different color) as a treasure that could be found in the Jungles of Tanaan.

awesome now give me back the sword I vendored!~
If the item has been misplaced in the time since it was originally obtained, there will be an in-game way for players to obtain the sword again.

Will it be like the vendors in pandaria?
It will likely be a vendor. Details are still TBD at this stage. (Blue Tracker / Official Forums)