Process is simple, have player 2 get all the items you want to duplicate, then have player 2 leave, the host then can access player 2's cabin drawers, with out removing anything, keep the window open, allow player 2 to rejoin, once joined, host can remove everything from the draw whiles player 2 keeps their items.
This would probably be an item duplication bug too. My friend and I (mainly me so far) have experienced that if a Serf player (me) tries to purchase a furniture or picture item from the street vendor, it causes a crash to happen. If you purchase any of the other items from the street vendor, it will keep all items in your inventory and it will then reset the items back on the street vendor for purchasing again. So if you had a large supply of gold (which we didn't since we're only in Summer Year 1) you could purchase Rare Seeds for 1000g, auto crash from trying to purchase the furniture/picture item and revisit the street vendor and repurchase it, rinse and repeat until it hits 7PM when the NPC despawns from the wagon window.
