Hello,
that will depend on where do you want to work with. There are countries that does not require a Flight Dispatch License but will train you to work as one of them.
if you don't know yet, there is a difference working as a Flight Dispatcher in Airlines, Ground Handlers and Flight support company. Most of the Airlines require an experience while Ground Handlers and Flight Support companies can hire you (some require license some don't) and provide initial training where you have to further expand your knowledge yourself.
But In my honest Opinion, If you insist to acquire license before working in aviation companies. You should go for F.A.A. Flight Dispatch license. Unlike other type, license has an expiration date where you have to retake all of the exams if you didn't work as Flight Dispatcher or related. (which cost again money
)
Feel free to ask.. i've been working in different Aviation companies and have seen their difference. (from Ground handlers ==> broker-Operator of leased aircrafts ==> airline ==> Flight SUpport company at the moment.
Enjoy Aviation field = )