Egg wash: 1 large egg plus 1 tablespoon water, beaten
In large mixer bowl, with paddle attachment, add 1/2 cup whole wheat flour, 1/2 cup all-purpose flour, dry milk and yeast. Mix 30 seconds to combine ingredients.
In microwave-safe bowl, heat water, oil and agave nectar to 120° to 130°F. Pour liquid into flour-yeast mixture, and beat on low speed 1 minute. Scrape bowl; cover and let rest 15 minutes.
Mix in 2 eggs, salt, onion and garlic powder; beat on low speed 1 minute. Add remaining 2 cups whole wheat flour, 1/4 cup at a time. Using dough hook, add enough of the remaining 1 cup all-purpose flour to form a slightly sticky dough.
Knead with dough hook 6 minutes on medium speed. Add wheat germ and 1 tablespoon chia seeds; continue kneading 2 minutes.
Place dough in large, oiled bowl, turn to coat top. Cover; let rise in warm place until double, about 1-1/2 hours. Lightly oil 18 standard-size, 2-1/2 x 1-1/4-inch muffin cups.
Punch down dough; divide into 18 equal pieces. Shape into a smooth ball and place in muffin cup. Cover; let rise until almost double, about 30 minutes. Carefully brush with egg wash and sprinkle remaining chia seeds on top.
Bake in preheated 375°F oven 15 to 18 minutes, until golden brown. Place rolls on cooling rack. Serve warm.