Title says it all. Ability to trade your unwanted collectibles. Of course only those that say "Purchased in Crown Store" at the bottom of the description. Zenimax would still get the same amount of money for the purchase. There would be no gold value. It would simply be a way to clear clutter and transfer your purchase from one account to another, kinda like the trading system that's already in the the game. It would also open up the possiblity of obtaining things that are no longer available, and the ability to trade one/multiple collectibles for another with other users. It would give unused retired colletibles a new home with users who can appreciate it because it's still new to them.
Edited by Soul_Banish on July 24, 2019 5:37AM
Example: You no longer care about that Frostmare, why not trade it to someone else in exchange for their Elder Dragon Horse and/or Elder Dragon Wolf Pup.
Adding second post to this: And the collectibles trade menu should only be available to ESO Plus subscribers.