I've been wondering about how international trafficking could happen, and I came up with live animal export ships:
Live export company Emanuel Exports loses its licence after deaths of 2,500 sheep
https://www.abc.net.au/news/2018-08-22/livestock-exporters-emanuel-have-licence-cancelled/10149576
https://www.businessnewsaus.com.au/articles/emanuel-exports–affiliate-has-export-licence-suspended.html
https://www.bloomberg.com/research/stocks/private/board.asp?privcapId=11064898
Would be a great way to smuggle people wouldn't it? Doubt anyone is looking too hard at empty ships on the return voyage either