Barbados Joe fairly clearly, but nevertheless I think it's closer than a lot of people. He was extremely dangerous but never unbeatable. I rank Tommy Ryan above him by a good margin.
I don't see why it would even be debated. Barbados Joe Walcott was one of the greatest welterweights of all time, arguably the greatest before Sugar ray Robinson. Jersey Joe Walcott was a fine fighter, but he would never feature in arguments about the greatest heavyweight. PS, being one of the greatest welterweights, is harder than being one of the greatest heavyweights. There is no weakness in a top 20 welterweight list!