Hi,
Errr .... it isn't a deep fat fryer! Whole idea of it. So obviously you cannot take raw fish immerse it in batter and "deep fry".
But it is good at frozen / fresh pre-battered items. For example I used it for a bought sweet and sour chicken and it was great. And as said previously in the thread it is perfect for chips.
You can also go dry panko breaded items as long as they are sticking really well, I've done some others now with a light breading by putting it on wax paper and in the deep freezer for 15 minutes before battering to make it cold, then quickly put on and back in freezer (in a ziploc bag with wax paper lining) for 1 hour after battering.
Then the batter stays on, hit it in the air fryer and it doesn't have time to melt away before keeping enough to stay. It works quite well. Obviously you can't do a tempura batter or anything, but for a light and crispy bread/cracker batter it works out well.