I used to fly the ATR ,and now fly the A320 Airbus Family.
On reflection the ATR is proberly easier in terms of descent managment , but its an argument that has been done to death here already.
Any competent turboprop pilot with a little bit of time on type will transition to a jet with no real problems , like most things it comes down to experience and familarity with the aircraft your operating.
They are just aircraft after all.
However imho the ATR was/ is more fun
