Preheat air fryer to 380 degrees F for 5 minutes. Rinse and dry mini potatoes, slice into 6-8 pieces each, smaller would need fewer slices. Make bite size.
Slice onions into medium chunks, put both into a bowl and toss with olive oil until coated. Sprinkle with seasonings and toss again.
Pour into air fryer basket for 20 minutes total tossing every 5 minutes. Check after 20 to ensure largest pieces are fork tender, if you want them crispier spray with olive oil and add another 2-3 minutes.