The same thing as people who violate state bans on high capacity magazines, certain gun parts, certain types of ammunition and certain firearms accessories. I bet you didn't know that depending on your state's laws, you could be arrested for purchasing those banned items. So naturally, sellers refuse to ship those items to the states that have those bans.
And of course, the person who illegally-purchases the abortion drugs through the mail from another states, would be fined or arrested.
Life's a bitch, ain't it?