In a medium bowl whisk together flours, seeds, salt, baking powder and wasabi. Add the oil and stir until combined. Add the water and stir to combine and create a dough. Turn the dough out onto a floured surface and knead 4 to 5 times. Divide the dough into 8 equal pieces, cover with a tea towel and refrigerate for at least 30 minutes. Preheat the oven to 450 degrees F. For very thin even thickness crackers, use a pasta roller. Flatten the dough until it will pass through the first setting and go to the highest number that your pasta roller will allow without tearing the dough. #5 is good. Place on a parchment lined baking sheet. Repeat with other pieces of dough until the sheet is filled. Beat egg and soy sauce together and brush each piece. Cut with rolling cutter to desired shape. Bake on the middle rack of the oven for 6 to 8 or until golden brown. Remove from the oven and place on a cooling rack. . Note: Baking times will vary depending on exact thickness of dough and oven temperature, so watch them closely. Store in an airtight container for up to 2 weeks.