I’m pretty sure that Himalayan Blackberries would not work well at all. They are too thick, they are not flexible enough, they dry out to hollow brittle canes, and they are covered with big nasty thorns.
I just had to add the clarification about native Trailing Blackberries because most people in the Pacific NW, when they hear “blackberries,” think of those big monster thornbushes that cover all open spaces they can.