Shapes gradually going from blue to orange

Regardless of what else you do this is most likely simply a case of using a 3D paint tool like Substance Painter. Your UV layout is going to need some love and attention, anyway, or else you may end up with hugley differently sized shapes and pretty odd seams and if you ever plan on producing this physically it would be even more critical to work out the exact proportions for vinyl cutting even just for masks. Other than that of course there may be more sense in designing the actual pattern in Illustrator, given that it creates separate shapes from the outset, which are much easier to handle. Presumable a simple greyscale gradinet applied across the board and then finely mangled through "Rcolor Artwork" and a bit of tweaking with individuall fills could probably do miracles for your design and after expanding the appearance it would be primetime ready without much redundant extra work...

Mylenium

I would think you would need to use a 3d Application  model the car and have it distorted your orange hexagons and blue design onto the car model body surfaces.  I do not know for sure for I do not create 3D models.  You would not want to create a Car 3D model using what is available Photshop's 3D feature. Adobe has some fabric design extension for Photoshop the may be helpful implementing your paint design.  Transferred the design onto a 3D object surface I would think is a job for a 3D application.

Best bet would be a script that randomly places the shapes, but is biased with values from a standard gradient.

Here is an example of a script. This will duplicate a red and blue hexigon layer in a random gradient across the canvas. For your file, if you have the shapes created, and they are all on separte layers, you can use the same sort of random code to change the color of the layer.

#target photoshop
var doc = activeDocument;
var redHex = doc.layers.getByName('Red Hex');
var blueHex = doc.layers.getByName('Blue Hex');
var widthHex = parseInt(redHex.bounds[2])-parseInt(redHex.bounds[0]);
var heightHex = parseInt(redHex.bounds[3])-parseInt(redHex.bounds[1]);
var sw = true;
var iStart = 0
var ranNum = 0;
var x = 0
var y = 0


for (j=-heightHex/2;j<doc.height;j+= heightHex/2){
    if(sw){iStart = 0}
    else{iStart = .75*widthHex}
    for(var i=iStart;i<doc.width;i+= (widthHex + widthHex/2)){
        ranNum = Math.floor(Math.random()*doc.width)
        if(ranNum<i){dupLay (blueHex)}
        else{dupLay(redHex)}
        doc.activeLayer.translate(i-parseInt(doc.activeLayer.bounds[0]),j-parseInt(doc.activeLayer.bounds[1]))
        }
    sw=sw==false;
    }

function dupLay (lay){
    doc.activeLayer = lay;    
    lay.duplicate ();
    
    }