This can be an extremely troublesome area as federal law is still different from state laws. That is, the transportation from outside of the U.S into the U.S. would certainly be a problem. Further, in many cases even transporting the cannabis between New York and New Jersey (as an example) could result in a felony. Due to such a problematic issue, the states where cannabis has been legalized has mostly legalized the legal transportation of legal cannabis within the state only. Each individual state varies greatly with the laws and legislation passed.