What changes
Module 09: object 0A65, byte 1, bits 2–3 = 01 (0D08, byte 0, bits 4–5 = 01 on a coded module). The first press unlocks only the driver's door, the second the rest.
Details
The 'selective unlocking' setting of the central electrics. The same choice is in the MMI menu if the item is shown there. The map comes in two variants — object 0A65 (module without long coding) or 0D08 (module with a filled long coding); Odyx uses whichever object the module has. Access code 31347; the module accepts changes only with the bonnet open. Rollback: write the object backup from the history.
Other options
This is one option of the “The first fob press unlocks” setting: only one can be active.