fuel pump purge valve is malfunctioning. at start up the injector rail pressure is not relieved immediately so you are getting fuel smell.
you can figure it out by simple key ON test.
in morning turn ignition key open rear hatch and check if there is fuel smell near rear seat bench. Start engine leave idling and check again, if smell is persistent for a while visit 3S shop.
Your vehicle is under warranty and 3S shall replace either the fuel pump or the purge valve in it for free.