This doesn’t apply to all helicopters because as previously stated in this and other threads not all helicopters have the pilots on the right for what ever reason. However, with the advent of the larger helicopters such as the S-55 series, the S-58 series and others in the Sikorsky line the pilot sat on the right because the main entry to the helicopter and the hoist were on the right hand side providing the pilot with a view to what was going on. IMHO
In a helicopter of that size the positioning of the pilot would have minimal effect on the lateral CG
or, on the propeller effect of the tail rotor.