What if modifier keys aren’t used…instead the direction of click-n-drag can determine selection type.
There is an option in architecture/3d modelling programs (Rhino, Revit, SketchUp) to differentiate object selection by either dragging from the Top-Left –> Bottom-Right or Top-Right → Bottom-Left.
Here is an example from Rhino (start – 2min):
Maybe TL->BR is the default node selection and TR->BL can include anchors (and perhaps even guidlines?) in the selection box.