I could be wrong here but is there not something about your entitlement to social welfare been based on the previous tax year
So you might get it for the first year but when you apply for the second year questions will be asked about the six months you were in France
and how you are able to afford that.
The SW is there to help people who have fallen on hard times it's not there to supplement peoples lifestyles even though it is abused by many both living and deceased
And then there's the simple fact that you may be unemployed but you have an income of €18k presumably from an ARF type thingy which will probably disqualify you from any means tested SW payment
Also just thinking you might not be entitled to two full payments of €208 but rather one full and a qualified adult which would total €346