One of Death Stranding 2: On the Beach’s main themes is all about forming and maintaining connections, whether between chiral networks or (especially) between people.
So, to reflect and honor this idea on the gameplay side, there are some quite literal mechanics on that topic, such as trading some items with local porters who randomly wander in the open-world – which even grants you a nice trophy for your collection, if you are into that.

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There is, however, a small problem. We have no tutorial or basic explanation of how exactly trading with other porters works or why we should do it, leaving many players very confused about this task. But fear not, we are here to help explain the details.
Here’s how you can take advantage of the ability to trade with local porters in Death Stranding 2: On The Beach and attempt to get a better item in return for something you don’t really personally need.
How to Trade With Local Porters

To trade with local porters (which are NPCs) is a much simpler task than it sounds. The funny thing is that the hardest part is actually finding them, as they can pop up randomly all over the map. In most cases, you’ll typically find them just after a station has been connected to the chiral network.
Your best bet is to find them early in the game is at the West Fort Knot location. As soon as you connect the station with Sam’s Q-pid, there will be two porters walking around. Now’s your chance to engage in a deal if you’re feeling lucky.

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To initiate a trade, approach them and drop any item from your inventory – it can be a ladder, a PCC, or anything that you are not going to miss anytime soon. To do that, open the main menu, go into the “Cargo Management” tab, and select an item to drop on the floor. This starts the trading sequence with whichever NPS porter you place the item in front of.
That is probably going to make the porter’s Odraddek spin rapidly to look at the cargo you just dropped, meaning that they agreed to trade with you. Now, all you have to do is wait until they pick it up and give you something in return.
Press the triangle button to grab what they offer, successfully concluding the trade.
This process will also unlock the “Porters Make the World Go Round” trophy the first time you successfully complete a trade. Nice work!
It’s up to you just how much you truly want to engage in this bartering system, since you don’t have much of a say in what the other NPCs offer back in return. But it’s still a fun exercise nonetheless and can net you something more useful than whatever you currently have on you that you don’t care much about.
Please note that the NPC porter can turn down your offer if you’re really offering total junk, so try to give them something nice. Be the porter you want to work with. I know that Hideo Kojima will be pleased with your efforts and willingness to connect.

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