Systemize Cross-Project Trust

I need to show a believable composite of two lighting conditions for the kitchen: the afternoon glazing we photographed and the proposed undercabinet task lighting we mocked in the studio. There's no rush, but the director will use this as a precedent. Diagnose whether the two images can be blended without rebuilding the whole scene, tell me which anchor (colour temperature match, shadow direction, or intensity) must be nailed first, and give the technique I'd standardize across projects so juniors stop overcompensating with global exposure tweaks.