You can select the elevation or section line and set the method to be 'Drawing' instead of Manual or Auto-Rebuild. This will create a 2D line version of the section or elevation. You can then trace and reference the 'Own Model Section' in to the view so you can manipulate the 2D data or trace over the live model in the background. This kind of goes against what Archicad is all about though.
ArchiCAD 4.5 - Archicad 26UKI Apple Silicon 5003
macOS Ventura (13.4)