Prepare an air fryer tray with a sheet of parchment paper.
In a medium saucepan or pot, add the water, butter, and salt and bring to a boil.
Stir in the flour and cook, stirring constantly, until the mixture forms a dough ball. (There will be a thin film on the bottom of the pan).
Remove the pan from the heat and add the dough to a large mixing bowl to cool for 10 minutes.
Stir in the eggs, one at a time, until combined and the dough becomes shiny.
Add the dough to a piping bag or Ziploc bag with a corner trimmed off. Working in batches, pipe 1 inch thick and 4 inch long strips onto the parchment paper.
Set the air fryer setting to 350 degrees and cook for 6-8 minutes, or until the eclairs are puffed, lightly golden, and cooked through.
While the eclairs cook, prepare the custard. Blend the heavy cream, vanilla, and powdered sugar with an electric mixer until stiff peaks form.
Mix together the pudding mix and milk until well blended in a large bowl. Fold in the whipped topping until just combined and chill in the refrigerator for 15-20 minutes.
Allow eclairs to cool fully, then slice the eclairs in half with a serrated knife.
Pipe or spoon the chilled custard filling onto the bottoms of the eclairs and place the tops back on.
Spread chocolate frosting over each eclair top and keep chilled until ready to serve.