Technically, States maintain the right to control customs and quarantine procedures on all trade coming across their borders.

The Feds are literally only there for CBP/immigration/Customs. Federal regulations only set the minimum level of friction for entry. States are technically free to increase it. In fact, this is even more humorous, because it isn't even "interstate" commerce til the second state depending on your level of literal interpretation you apply.

Not that I agree with it, but I'd wager there is nothing unconstitutional here. State border crossings are well established delegated powers to the State.