Preheat oven to 400 degrees F. Line a baking sheet with foil or parchment paper; set aside.
Place toasted flaxseeds in a spice grinder and pulse until ground to a fine powder.
Place whole hemp seeds in spice grinder or small food processor and pulse until ground (the whole hemp seeds may not appear as finely ground as the flaxseeds).
In a medium bowl, combine ground flaxseeds, ground whole hemp seeds, flour, the 1/2 cup oats, sugar, baking powder, and salt.
Using a pastry blender, cut in butter until mixture resembles coarse crumbs. Make a well in the center of the flour mixture; set aside.
In a bowl, slightly beat egg white; stir in yogurt. Gently fold in berries.
Add berry mixture all at once to flour mixture. With a fork, stir just until moistened.
Turn out dough onto a lightly floured surface. Knead by folding and gently pressing dough for 10 to 12 strokes or until dough is nearly smooth.
Pat or lightly roll dough into a 10-inch circle. Cut into 12 wedges.
Place wedges 1 inch apart on prepared baking sheet. Brush tops of scones with milk. If desired, sprinkle lightly with additional oats and/or flaxseeds.
Bake for 16 to 18 minutes or until golden brown. Serve warm.