No, they don't need to follow the local law. I can buy whatever I want from anywhere in the world and the company doesn't need to follow anything other than the law of their home.
These are very significantly different cases:
1) a foreign customer buying
2) a foreign company selling
In the first case, the company follows their home law only. On the second case they would have to follow the local law of the customer's country too
These are very significantly different cases:
1) a foreign customer buying
2) a foreign company selling
In the first case, the company follows their home law only. On the second case they would have to follow the local law of the customer's country too