Colormap Effect in 3D

Is there any way I could use the Colormap effect or any other 2D effect in 3D to make a game a bit more stylistic?

Perhaps i could use some script or there might be a way already implemented?

Is impossible to use any kind of 2D rendering behavior for 3D environment since they use different engines that work independently from each other

i always wanted to use the colormap effect in 3d…itd be very OP in making the games look nice