The French Exclusive Economic Zone flag uses the set heraldic pattern of the international Exclusive Economic Zone flag. But only the colours white and green are used. The pattern of the national flag of France is conserved and repeated.
Switching the colours of the French flag with green or black would naturally confuse persons as to which flag it belongs to. France's colours and pattern are distinct when combined but her pattern is rather common place as many nations follow that vertical tri-bar pattern. But in this arrangement it can be more easily discerned that this flag is in some way connected to France.
Likewise French nationals born in the France's Exclusive Economic Zone can use this flag.