Woocommerce : Showing just only 2 values attributes product

I know that I can create attributes of color, size and etc. But for some reason, I had to combine 3 attributes into one and then displayed them differently.

Now, I’ve the attribute with the values :

pa_mixed : Red, Blue, Green, S, M, L, Children, Adult

But on the front end I have to display like :

Colors : Blue, Red

Size : M

Aged : Children

So far I have tried :

    if (!empty ($product->get_attribute('pa_mixed'))):
        $pa_mixed = $product->get_attribute('pa_mixed');
    else:
        $pa_mixed = "";
    endif;

    $size = array('S','M','L'); 
      
      if ( in_array( $size, $pa_mixed ) ) {
         //colors attributes
      }
      //etc

And finally I got lost

please help me to find the right way, thank you