PhysicalConnectivity/src/main/resources/assets/phycon/models/block/cable_diag_corner_xz.json

{
  "textures": {
    "corner": "phycon:block/cable/color/cap_end"
  },
  "elements": [
    {
      "from": [6, 7, 6],
      "to": [7, 9, 7],
      "faces": {
        "north": {"texture": "#corner"},
        "west": {"texture": "#corner"}
      }
    }
  ]
}