Preheat the oven to 350 and grease a donut pan very well.
In a medium bowl, whisk together the coconut flour, sweetener, poppyseed, baking powder, and salt. Stir in the eggs, ghee, lemon zest, 6 tbsp water, and lemon extract until well combined. Add additional water if the batter is very thick.
Divide the batter among the wells of the donut pan. If you have a six-well donut pan, you may need to work in batches.
Bake about 15 minutes, until the donuts are set and firm to the touch. Remove and let cool in the pan for 10 minutes, then flip out onto a wire rack to cool completely.
Glaze
In a small bowl, whisk together the powdered sweetener and enough lemon juice to achieve a drizzling consistency. Drizzle over the cooled donuts.