Front camber does not change much during suspension travel on this type of strut front with only a lower control arm, so the camber adjustment should be simply adjusting the cam bolt attaching strut to knuckle.
The rear, as mentioned previously, has a long lower arm and a short upper arm, so camber changes a lot with suspension travel. I know of 2 ways to adjust it to compensate for lower stance. 1, buy one of the adjustable length, aftermarket lower arm kits. 2, buy a urethane bushing that has an offset center hole for LCA inner bushing (I did this with a Whiteline bushing and a press). Also, on a 4th gen lowering thread, some guys were swapping to Legacy struts and Legacy upper rear control arms which helped camber. I dont know if those arms are longer or how they helped though. My air struts have 4inches of travel so I set my alignment at where I normally have it (1 1/2 inches up from bottomed out), and rear camber is at 1.5 degrees to promote planted cornering. Outbacks can handle pretty well if set up correctly. I was surprised!