A drizzle of Cheng Chi Golden Natural Shallot Oil — not much, a spoonful, or spray it on — and it is perfect.
This is Spanish mackerel done in an air fryer. Most people find it smells strongly of fish; with shallot oil, that changes.
The result: no fishy smell at all, just the fish itself.
Something this useful is worth getting hold of.
This is the one https://www.shallot.com.tw/shop/html/?44.html