An attempt to organize a team tournament between countries!

That's correct. If we had more combined teams or if the teams weren't so small, this rule wouldn't be necessary. And it's wrong to prohibit one team while allowing another. Reducing the number of participating teams just to prevent a player from being repeated wouldn't be acceptable to the sponsor. Ideally, small teams should be combined with other small teams, but as we can see, there are still problems with that. However, if we can combine them, we can reconsider this rule. For now, I don't see any other options. If there are any specific suggestions, I will consider them.