An Adventurer Traveling Through Three Worlds

Being able to travel back and forth with a time travel system, what? There is a loophole in the system! You can hold it in your mouth and bring out items from both worlds! Take the artificial pearls from the real world to another world and exchange them for gold and bring them back, and you will get twenty times the profit at a time! Now I, Bian Zhiheng, am going to post it!