I believe MIDI learn is Global settings for the instrument. But perhaps you can use this: Manual section "3.2.10 MIDI controller configuration."
If you export a MIDI Config i guess you can give your friend a copy to import.
I haven't used this feature. But if it works like i hope and think, then you can actually make a map for each preset. I guess it require both your controllers have the same CC numbers set up for each control. And if the MIDI mapping is different for each preset, then a new map has to be exported and posted and then imported for each new preset.
As said i don't know if this works, but i thought i would give you this input, in case it do work, and there's no other options. Perhaps it's worth a try.
BTW: I would export and save the current settings also before making changes, so it's possible to get the same settings again.
It would be a great feature though, if there was an option to save a CC mapping with a preset. Perhaps to export a Midi map when a preset is saved, and to load the map as the preset is loaded. Don't know. Perhaps it need some thinking.