score:4
The rules on paintball eqiupment is demonstratably not the same internationally. Here's some random examples that I could find information on:
Your best bet for information in each specific case is to contact either or both of the country's Customs and any local paintball organization that you can reach. The former will give you official information if paintball markers do not fall into any grey areas in the local laws (which they can do) while the latter are more likely to be able to answer your question in a practical sense.