So our world you have wormholes, they aren't "tunnels", just "doorways" of sorts between two systems.
The network connects a small portion of our galaxy, some 500 solar systems in total.
Technology is ahead of ours but not too fantastically so, torch ships exist but they reach at most something like 10% of C, nobody can reach "true" relativistic speeds like 90% of C or so.
I did some calculations and seemingly it takes some 20 days or so to travel across a solar system the size of ours, travelling across the whole human space would take at most 3-4 years (assuming you are "dodging" the planets and just going straight for each system wormhole toward the next without stopping)
In that scenario, what kind of resources would people bother trading? Would be there anything you can't find in a singular solar system and need to go to another to find?
I am not talking about art, people, ideas, equipment, or ships, I am asking what resources are worth shipping.
To be precise, since I used the science-based tag, I am asking what kind of materials you might find in one region of space that might be lacking in another, and would be useful enough for humans in general to be worth shipping.