Chillaxing © 2015 Chantal-Hélène Wagner
Maybe "Hip Hop" is not the best descriptor for these guys' style of dressing - a flavor of hip-hop? It's interesting to spot the youth culture currents in the city...
I think it's both moving and interesting to see youth codes get worked and reworked, and it's been perhaps less easy in France than elsewhere to do so due to the soft-edged conservatism in place, but things are changing.
So, what is most likely to take place is that you will happen on isolated groups rather than on a really visible trend running throughout the city. There are however hip hop festivals in France which would be the places where everyone interested can touch base.