Well I have the first on your list Airnimal Rhino White – running 1×8 Alfine hub, which I love. Taken it to Swinley a few times. It’s not light – 10kg sounds optimistic, packing into the airnimal suitcase is not easy and there are no real 20″ MTB tyres (I now run Marathon plus which are fine for trekking). That said, it’s a lovely ride and can do modest luggage. If you live near SL3 you are welcome to try it.
How much off-roading will you really be doing? I ask because there are several other options for folding/packing:
Bike Friday New World Tourist – not cheap but you can tow the case
Birdy anything
S&S coupled retrofitted steel frame e.g., Genesis IOID – this would probably be my first choice to be honest if you are wedded to 26″ wheels.
I guess a lot depends on how many times you will be packing it. I like the S&S couplings but went Airnimal for rapid folding to throw in the car. It’s a good compromise.