Hey!
I am not sure if I have put this in the right place as I don't really think it's an exploit, but please feel free to point me in the right direction if there is somewhere else more suited for this post, or if it has already been posted I will be happy to take it down.
This is not a transmog farming post, but if you're like me and you love your mog, then if you don't already know this or haven't tried it, it could be a nice little surprise for you.
If you create a Class Trial and log into that Character, the items that they are wearing become part of your transmog items if you don't already have them. Some classes also have a chest in their inventory of other items (weapons, cloak etc) in case you wanted to change specs.
I could be super late to the party, but I didn't want to not say something just in case there is someone out there like myself who didn't know about this.
Happy mogging!