All Note 20 Ultras have the s pen located on the left hand side.
This is possibly due to the camera module.
It took a little while to get used to from using the N10 + 5G for a year where the s pen is on the right hand side.
The s20 line do not have a built in s pen.
Current Phone ~
Samsung Note 20 Ultra 5G SM-N9860_256Gb SnapDragon 865+
Samsung One Ui 3.1/ Android 11.