A lot of places try to manage that by holding retailers responsible - making it a fine-able offence to sell, for example, RF emitting gear that breaks local regulations. This _kinda_ works where most of the retailers are concerned about their reputation and are in the local jurisdiction, but breaks down _fast_ when thinks like AliExpress are taken into account.

(And it even occasionally fails spectacularly in cases where it _ought_ to have worked OK - people offloading lithium battery charging safety to large locally represented brands like Samsung instead of self-importing Xaiomi or Doogee "brand" phones directly from China...)