That's a good question and one I had to look up. As long as you activate the commanders ability before combat, then the pump effect and annihilator 1 bonus on scions and spawns will stick around even if they change creature types later in the turn(aka with deceiver of form). So you'll be able to get the best of both worlds. Now, if you reverse the order(wait until after dof trigger to activate Azlask), then you're right, all your creatures would not be scions/spawns and wouldn't get the added bonus

@@CyclonicThriftahh good to know