For two months, I wouldn't worry too much about number of flights, transfers, etc. But I've been lucky.....never lost or had anything damaged during air travel (although I've had gear stolen at my destination).
I'd try to take 2 LEIs plus a foil kite (no more than 3 total). In my experience, you can usually rent a functional light wind TT or surfboard, so I'd leave those at home. I'd probably try to travel with a smaller, high wind TT and a foil board setup.
If it's a tropical destination, leave the wetsuit at home; a light weight steamer top with board shorts should suffice in "colder" conditions. I've known people who leave their pumps at home and simply borrow one from another kiter on the beach. Personally, I want my own pump, but I'd take a smaller, old style pump (non-WMFG) to save space.
That alone would be a lot for air travel. I'm sure I'd pay extra fees for weight, etc. But 2 months is a long time if it's a dedicated kiting trip, so take what you need.