Way 1 :

  1. Choose the model that you want to edit
  2. go to material tab, scrool down to “Reflection” section
  3. change from vehicle_reflection.tobj to fuzzy_reflection.tobj
  4. Export and pack

Note : this method will REMOVE all the relection on the part from sunlight

Way 2 :

  1. If the texture has AO, change the alpha channel to more darker
  2. If the texture has plain color you should make an alpha channel
  • Open your .tga texture file into photoshop
  • Head to channel tab ( if you dont see this menu go to Window > Channel )
  • make sure to click on the alpha part
  • press Win + L to open Levels tab
  • adjust the value to what you want
  • follow the lines on the image above, move the white slider to left to make it darker
  • save it
  • done

Result :

Before

After

Credits to : https://forum.scssoft.com/viewtopic.php?p=1507834#p1507834