[stephenr]

As a "freelancer" living in/working from a country where there is no legal concept of being a sole-trader/freelancer/self employed without a registered business entity, I would say this:

It's not your problem. There is exactly one thing your company can do (which defeats the whole purpose): open a branch office in their country and employ them as a regular role.

If you're not doing that, how they issue you an invoice is irrelevant to you.