On GT Sport we can only set Steering to be done from Left Stick, Directional Buttons or using Motion Control Function.
In order to use Right Stick for Steering on GT SPort, we can use PS4 Accessibility Settings. On PS4 under "Settings / Accessibility / Button Assignments" we can swap Left and Right Sticks. Tested this on GT Sport and works using DualShock 4 Wireless Controllers.
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