Your walls (simple or composite) will be using a building material for the 'Structure' (what you will see in plan).
In your Building Material settings you can choose the type of fill that you want for the cut fill and also the foreground and background pen colours used for that fill.
This is what you will see in plan.
You may need to adjust display order to pull the wall on top or send other elements to the back (generally the default order is pretty good).
Barry.
One of the forum moderators.
Versions 6.5 to 27
i7-10700 @ 2.9Ghz, 32GB ram, GeForce RTX 2060 (6GB), Windows 10
Lenovo Thinkpad - i7-1270P 2.20 GHz, 32GB RAM, Nvidia T550, Windows 11