taps head hot and cold

Hi, just had a new bathroom fitted, and to my annoyance, the waterfall style faucet dribbles out the hot water, only when the cold tap is fully open does it work. My plumber then installed a 2 bar pump, but it still didn't flow properly and dribbled out. The manufacturer says i need 3 - 5 bar...

I've just purchased this Swirl Magellan bath mixer tap from screwfix to replace an identical broken tap. I've noticed that the Hot and Cold tap heads are on the opposite sides. I don't want to start changing all the piping, so assume there is a simple way to switch the tap "heads". Can anyone...