As long as they are regulated, there's no problem dealing with them. Most of the Forex brokers do not have license from each country since Forex trading is done online.

Yes, there are tons of brokers that offers Forex trading to any countries without applying any licenses to the specific country where their clients situated.

I think it's their choice either to avail the license of each country or not. For me, it doesn't affect their reliability. A broker that has no license to operate their business to the other countries is not a problem as long as they're properly regulated.

For me, license is very essential and it shows the integrity of a broker. If I were you, I won't invest to a broker that has no license to operate their business in any countries. A broker that has no license cannot be trusted.