qgis - Creating leader lines for moved labels

With a lot of help from gis.stackexchange.com I've created leader lines for point symbols. The lines are based on a geometry generator symbology:

Shortening line geometry using expression dialog in QGIS?

Now, I want to implement leader lines for moved labels. It's very importent to me, that the lines start at the center of the labels and end at the point coordinates (or vice versa).

-- Geometry generator:
make_line(
    make_point(label_x, label_y),
    $geometry)

Once again, the lines are covered by the labels:

Is there a way to address the label boxes and shorten the leader lines? I suppose this is quite a tricky question :/