Slaves were mostly brought in before independence, by british flagged vessels. Even after the slave trade, slaves were brought in by Jean Lafitte the pirate and Jim Bowie. They would be landed at New Orleans, picked up by the federal customs agent, then auctioned with federal title as contraband. Jim Bowie’s thugs would nudge as necessary to discourage anyone else from bidding, so his very low bid would always win.
Just to be sure you are up on your Texas history makers.
Oh...I know my history, but what’s your point? Thomas Jefferson was a slave owner as well. So was Ulysses Grant. Jim Bowie also had lumber mills. Business is business...especially when legal.