For the batter: Blend the flour, sugar, and salt in a food processor or blender. Add the milk, water, eggs, butter, and vanilla extract, and process until smooth. Set aside for at least 30 minutes.
For the fruit: While batter rests, hull and halve the strawberries. Toss with blackberries, sugar, and orange liqueur, if using, in a medium bowl; set aside.
For the filling: Whisk the cheeses with the sugar, orange zest and juice, and the vanilla extract.
To make the crepes: Heat an 6-inch nonstick skillet or crepe pan over medium heat until a drop of water bounces and sizzles briefly on its surface before evaporating. Quickly pour in about 2 tablespoons of crepe batter and swirl it to coat the skillet evenly. Cook until the batter sets, about 30 seconds. Flip the crepe and cook the other side until just barely golden. Repeat with the remaining batter, stacking the crepes as they cook.
Place 1 tablespoon of the cheese filling on the lower left-hand corner of each crepe. Fold crepe in half, then half again to make a triangle with filling in the tip. Repeat with the remaining crepes and filling. Stack filled crepes neatly on serving platter (or hotel pan). (The crepes can be prepared up to this point a day ahead, covered tightly with plastic wrap and refrigerated overnight.)
To serve: Preheat an oven to 250 degrees F. Cover crepes with foil and warm in the oven until heated through, about 10 minutes.
Spoon the macerated berries over the crepes and serve.