IT will be surly very expensive to have visas and accomodation at three different countries
People would visit a place of two - most of the people will be middle class like me they won't be able to afford the 3 country stay
I dont think that fans will have to visit all three country to watch their teams play during preliminaries, playoff and finals. Take
IIHF World Championship 2023 as example, it is held in two countries also, two countries that are separated by sea, but finals will be held only in one country. It might even be, that during preliminaries, playoff and finals, two team will not even leave country.
Watching sports live is always expensive, but such tournaments happens only once a year or two, so you have plenty of time to save money, do booking research and get best offer. Average class watch such tournaments at home. I think an average fan can afford only few tickets, but only wealthy person visit all games, so visas, accommodation and tickets wont be problem for him.