Place the chickpeas, red onion, fresh parsley, zucchini, ground cumin, salt, flour, and chia seeds into a food processor and pulse everything until the mixture just comes together and the chickpeas are in loose, bread crumb sized pieces (do not make a puree!). Scrape the sides of the mixer as needed, to help everything pulse evenly.
Once pulsed, scoop the mixture into 16 balls, and brush with olive oil.
Select Air Fry and set the temperature to 400°F / 205°C and the time to 10 minutes.
When prompted to Turn Food, flip the falafel and brush again with olive oil.
While the falafels cook, make the tahini sauce. Grate the garlic into a small bowl and pour over the lemon juice.
Mix in the tahini, and water. The mixture may look a little odd and split at first, but keep stirring and it will come together to be a smooth silky sauce.
Season the mixture with salt.
When the falafels have cooked, serve with the tahini sauce.