If it's the same engine bay layout as the e208, which seems likely, then there will be physical room under there but I wouldn't want to leave the cable there when driving. If you can get 11 kW then you definitely have the 3ph cable. I always thought it was a bit odd that Peugeot made the 3ph on board optional while it was standard on the Corsa. You think they'd have kept those the same.
The inverter and charger assembly is under the plastic cover mounted on top of the motor assembly near the DC

C converter.