For the crepes: Preheat the oven to 400 degrees F.
Whisk together the eggs, butter, heavy cream, sugar, orange liqueur and orange zest in a large mixing bowl. Whisk in both flours until incorporated and a pourable batter forms. Let the batter rest at least 10 minutes and up to 1 hour.
Heat a 9-inch nonstick crepe pan over medium heat, then add a thin layer of batter (about 1 cup). Spread around the pan to cover. Cook until the top is dry and edges begin to curl up, about 1 minute. Flip and cook another minute. Repeat to make additional crepes using all the batter. Set aside.
For the souffle batter: Combine the heavy cream, butter, orange liqueur, flour, brown sugar and orange zest in a small saucepan over low heat. Cook, stirring constantly, until thickened, about 5 minutes, then remove from the heat. Meanwhile, whisk the egg yolks in a medium bowl. Whisk the egg yolks into the warm mixture in a steady stream. Set aside.
Place the egg whites in a stand mixer and beat to soft peaks using the whisk attachment. Fold the egg yolk mixture into the egg whites.
Place a crepe on a parchment paper-lined rimmed sheet tray. Spoon a 4-ounce ladle of souffle batter in the middle. Fold in half, like a taco. Repeat with the remaining crepes and souffle batter. Bake until the souffle filling puffs up a little, 12 to 15 minutes.
Dust with powdered sugar and sprinkle with orange zest.