How can I customize the 'sync' method?

Question

Laravel

I'm trying to use this method to update cart data. Everything would be fine, but the cart table is built in such a way that the product id is repeated, because the product has a color attribute. That is, this option will not work because the id is duplicated.

$arr = ['43'=>[ 'product_quantity'=>'1,'product_color'=>'red'], '43'=>[ 'product_quantity'=>'3,'product_color'=>'green']];
$cart->product()->sync($arr);

As a solution, I have the opportunity to create an id-color field, and it will already be unique. Is it possible to force this method to synchronize on the id-color field? If not, can you suggest other options?