You should be able to grow some greens (lettuces, mesclun, etc) in part shade but nearly all other edible crops will prefer full sun and many require it. As to soil pH, it depends on the specific crop and the pH levels but most plants tolerate a range of pH, some quite wide. If soil is only moderately acidic (6.0 or above), as most PNW soils are, you should be fine. Otherwise berries, especially blueberries (Vaccinium sp) tolerate acidic soils, but will need sun to flower and fruit well.

If you are limited with inground planting by soil/sunlight conditions, you might consider constructing raised beds in more open, sunny areas or grow your veggies in containers.