To compare
standard sapph 2wd abs hub knuckle
xr4x4 abs hub knuckle

both have similarities but there are some differences

hubs are same thickness but different in OD size xr4x4 is slightly larger

Same size wheel nut threads --> Correct

Same size inner hub the 108 --> Correct

xr4x4 has ​​​​​bigger slot or hole for shock strut but the bolt size is the same --> Standard Sierra and 2wd Cosworth have a 45.5 mm thick strut, all 4x4's are 51 mm thick.

mounting holes and position for the brake caliper is the same --> Correct, the mounting holes are the same on all Sierra's, except for the 2wd Cosworth.

The tie rod end holes are the same size but positioning is different --> Correct, all Sierra's use the same tie rod ends

the xr4x4 carrier is larger in height compared to 2wd --> Correct, the 4x4 struts are shorter to compensate for this.

both retain ABS sensors

xr4x4 obviously is open to allow for drive shaft to pass through whereas 2wd is covered and retains a nut to hold the drive spindle

Xr4x4 has pinchbolt system and 2wd has castle nut system --> Correct, where the 2wd has a tapered hole and the 4x4 a straight hole.
The hole on the 2wd appears offset to the carrier whereas the xr4x4 appears centered but cannot be sure --> This is actually one of the things that determine the caster angle and is a reason why 4x4 and 2wd parts should not be mixed as it messes up the driving feel.
It also appears that the xr4x4 hole sits slightly further away from the carrier. Please can someone confirm to verify my findings --> This could be the case. The XR4x4 has a very wide front track, much wider than the 4x4 Cosworth.