After some in house discussions, we're going to allow for Premium Vanities (purchased with Platinum) to be stashable in the near future. What does this mean exactly? It means that when you buy a premium platinum vanity you can now shuffle it around between your characters, as well as stash it to free up some inventory slots. There are probably some questions, and I will answer when I have some time, but I'll get the ball rolling with some questions I presume will come up.
But what about gold purchased vanities?
For the time being this makes sense to leave as a gold purchasable, non stashable item for the sake of the economy. It's healthy to have somewhere that can take gold out, and it also allows us to preserve the integrity of the achievements system. If everything was stashable then new characters on an account wouldn't need to work at it to get the associated achievements and styles on said character.
As always our development and plans can change, so this is not set in stone. It is however, the appropriate thing to do at this point in time.
Can I trade vanities with my friends?
Only world drop (Drops in 3D missions), Nightly Reward, and potential Ally oriented vanities will fall into this category. Premium purchased vanities and gold purchased vanities will not be tradeable.