How to change Product Fields position on the page?

Default position of the Product Fields uses the WooCommerce hook woocommerce_before_add_to_cart_button, so the fields appear before add to cart button.

You can use any other hook that WooCommerce offers on the product page, or even use any custom hook of your own, if you add this to your theme.

Here's the example how to change the position to woocommerce_after_variations_form hook:

add_filter('wccf_product_fields_position_hook', 'wccf_product_fields_position_hook_change', 99, 1);

function wccf_product_fields_position_hook_change($default) {
    return 'woocommerce_after_variations_form';
}