> Even if the company is not tax resident of said countries ? Mind pointing me to the laws/countries.
Yes. Broadly this falls under CFC ("Controlled foreign corporation") related laws. Taxation of the foreign entity could exist at either the corporate level (i.e. some domestic entity owns a low tax subsidiary in some tax haven), or the shareholder level (i.e. you own shares of a company in some tax haven).
> Any estimate?
Depends on the business. Some things you can't run through a low tax entity, others you can. If you sell an app on the app store, that would be relatively easy, for example. But you'd have to fly to the jurisdiction to sign the contract + probably have a local director.
The problem with these structures is not the set up cost. It's the cost of defending it in court if the tax authority of your residence country comes after you. And they do.
If you can't afford to defend yourself, you might as well not set it up.
> Some EU countries have tax laws that look through said structures, attributing earned income to the shareholders. That's one reason.
Even if the company is not tax resident of said countries ? Mind pointing me to the laws/countries.
> doing it right also requires a great deal of additional paperwork (+ extra overhead expenses)
Any estimate ?
This is very informative. Thank You.