We hardly ever find perfect locations in the garden for one reason or another but, generally speaking, yes, morning sun and afternoon shade is best. A southern or eastern exposure with afternoon shade would be great. I have several japonicas on a northern exposure with full shade (but it is "bright" shade).

If you can find these sometimes elusive "perfect/optimal" conditions, ALSO look for areas that can protect them from winds in the summer in hot areas or protect them from sun-scald in the wintertime. Summer winds can kill (dry out) camellias down here (may not be an issue for you in VA). But on the other hand, in cold locations, the leaves can sometimes suffer from sun scald in winter when it is freezing and the very, very early morning sun hits them.