It is not as simple as 'we all flew Cessna's from the left'.
Whereas with conventional collumns your whole arm is involved in steering, with the Airbus sidestick it's only the wrist that moves the stick. This requires very delicate input and it all comes down to fine muscle movements in your wrist, without the stabilizing guidance of the rest of your arm. This can be quite challenging if you are not used to use your left hand for delicate matters (like writing!)... initially there is no finesse whatsoever.
About twenty flights before you start greasing again.