As configurable as Max is, there are a lot of colors that you can't modify. I don't think you can change the color of the 'edged faces.'
One workaround might be to temporarily make your terrain a medium or light gray. That way the contrast between the edges and the polys will be less dramatic. That might help somewhat.
Rob Holmes
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3ds Max (2023-2025), V-Ray 6.2, Ryzen 9 3950-X Processor, DDR 4 128MB, Gigabyte Aorus X570 Master motherboard, Sabrent Rocket NVMe 4.0 M.2 drives, NVidia RTX 4090, Space Pilot Pro, Windows 11 Pro x64, Tri-Monitor, Cintiq 13HD, Windows 11 x64
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