Are we talking Flight Dispatch qualification? Or Dispatch as in UK (actually ramp agent, GH coordinator, whatever he gets called in all the other parts of EU)?
If it is about FD, not having a Flight Dispatcher certificate won't get you anywhere in US, FAA requires it by rules. It is less strict in EU, every other CAA figures out the requirements on their own, Czech CAA for example will require you to pass their certification based on ICAO FOO/FD training requirements (ICAO Doc 7192 D3), while Latvian CAA barely knows what a Flight Dispatcher is.
If you will choose to go for a Flight Dispatcher training I would recommend you to choose one of the FAA certifying schools, USA only, however there are possibilities to study online prior to coming to reduce the costs of living in US. (I assume you are from EU or North Africa at least judging by your location sign
)
FAA certificate (license, call it whatever you like) will be accepted pretty much in every country (may anyone correct me if I'm wrong).
There are some random IATA trainings / (generic) aviation training facilities trainings provided according to previously mentioned ICAO document, but I can't really tell anything about those, generally certificates issued after such kind of training are less valuable than FAA.
Coming back to your original question - yes, having a Flight Dispatcher certificate should give you a head start before applicants without one for any FD job out there.
But then again, I don't really know your background dear sir, employer might hire you for what you already accomplished, and send you to the training tailored to their needs.
I hope I answered your question. If anyone deems my words wrong, please make sure to correct me, I'm still learning
Brgds,
J.