How to know component's offset when making custom footprint
The origin of library parts should be the centre, I.e. the point at which the P&amp;P nozzle should pick up the device.  I’m not certain about KiCad but some PCB software allows the user to select either the library origin or the apparent centre of the device.
When setting up a P&amp;P machine the operator will always carry out a test run to ensure that each component is aligned properly.  Another thing to bear in mind is the orientation of footprints in the library - the ideal being that 0 degrees rotation means that the component is moved from tape (horizontal with sprockets at the top) to the PCB without rotation.  In reality this may be different depending on the design of the P&amp;P machine and orientation of the PCB, and for non T&amp;R parts.  P&amp;P operators are entirely used to irregularities; provided that they can identify the pads on which the component belongs and the orientation, if it matters, then all will be well.