I think it's correct to say that not all countries have/require a government-issued dispatcher license but if one is required, doesn't it need to be issued by the government of the country in which you'd be dispatching ? Or maybe there are license conversions available ?
If you're thinking of coming to the USA for school, here's a pretty civilized forum with a very active dispatcher forum where training is discussed in detail:
https://forums.jetcareers.com/forums...l-dispatch.83/
[I have no affiliation with said forum]