Can I transfer my items to another world?

No, items are bound to the current world and cannot be transferred to another. The only exception is if you copy your village to a Casual world. Then all items that can be transferred will be moved to the Casual world and removed from the original world. Those which cannot be moved (mostly due to incompatible world settings) will remain on the original world. You will receive a report telling you which items could not be transferred to the Casual world.