You shouldn't need to add coding to each mirror
If you go into the Central Electrics Control Module in VCDS you will see an option that says something like "mirror dip with reverse" just tick that.
Then to set the mirror, turn on the ignition, put the mirror control lever to L, put the car in reverse, set the mirror to the position you want then turn the control back to 0.
Drive forwards about 50m, turn mirror control to L, then put the car in reverse, the mirror will then dip to your pre-set position. When you then take the car out of reverse and switch off the ignition the mirror should return to the normal position.
Hopefully that will help. If not then you must have done something wrong with the coding.
You do have electric memory seats don't you?