Does this work outside the United States?

Yes. A ladder can be created anywhere in the world, and no country is off the list. Deuce fills city by city rather than country by country, English-first everywhere. Court fees, booking and eligibility are whatever your local courts already do.

A ladder also does not have to be a club. The organizer sets the scope: one club, several clubs, a city, an area inside a city, a region or state, or a whole country. It is published on the ladder page so you know how far you may be traveling. Rule 1.10.