We picked up our sedan a week ago and I have now found out that this function is missing, despite that ours has got all the option packs we can get over here.

The dealer tried to no avail to get it to work. There is in the infotainment an option missing: "Safe seat settings to key" which need to be ticked for this to work.
I asked the dealer to get onto Skoda to see if this is correct. Ours fully specked out has got all the hardware required, so this is a pure software issue.