Export config from 2011, read through and copy only needed config. Safest way.
You can try import the whole config from 2011, but you might get trouble with port numbers, different switches and so on.
Agree with Quackyo, and even then be prepared for possible differences in the way the hardware works. I recently tried to move config from a hAP AC Lite to a hAP AC. I thought it should be pretty close and didn’t expect to see any differences. I ran into real issues and differences with VLAN config that took a day or two to get sorted.