Woocommerce Hide Paid Shipping id qualify for free.

hide_paid_if_free_available

<?php 

/**
 * Hide paid shipping methods if free shipping is available.
 */

 /*
$name should be the part before the : separaor
 */
function wpe_find_shipping_method($name, $rates){
    /* The rate could have any suffic, find by part before the : */
    foreach($rates as $fullName=>$value){
       $parts = explode(':', $fullName);
       if($parts[0] === $name){
           return [
               'name' => $fullName,
               'value' => $value,
           ];
       }
    }
    return false;
}

function wpe_hide_paid_shipping_when_free_shipping_available( $rates, $package) {
    
    $free = wpe_find_shipping_method('free_shipping', $rates);

    if($free){
        $newRates = array(
            $free['name'] => $free['value']
        );

        $local = wpe_find_shipping_method('local_pickup', $rates);
        if($local){
            $newRates += array($local['name'] => $local['value']);
        }
        return $newRates;
    }else{
        return $rates;
    }
    
}
add_filter( 'woocommerce_package_rates', 'wpe_hide_paid_shipping_when_free_shipping_available', 10, 2 );