This is a long-time feature and I know it's probably been asked plenty before, but what is the point of:
-Locking cosmetic items to classes/class branches? (I bought it, why does it matter under who if it's on the same account?)
-Making some event-based cosmetics and chairs untradable instead of movable through the account. (Again, I earned the item through the event. Who under my account uses it after that point shouldn't matter.)
-Overlaps of the first two, you earned the event item and you can move it but only in a class-locked way.
Cash Shop Inventory Transfer events have happened before and prove this isn't a hard limit.
If it's about money, I'm less likely to spend money if I know I could end up with a clothing item I want to send to another character but won't be able to for an indefinite period of time.