Hide checkout shipping fields section for specific shipping method in WooCommerce

PHP is not the way as this an event on a "client side" (not on "server side"), so it requires to use jQuery. So to hide shipping fields section for a specific shipping method, you will use the following:

// Auto Show hide checkout shipping fields section based on chosen shipping methodsadd_action( 'wp_footer', 'custom_checkout_field_script' );function custom_checkout_field_script() {    // Only on checkout page    if( is_checkout() && ! is_wc_endpoint_url() ):    // HERE below define your local pickup shipping method    $local_pickup = 'local_pickup:1';    // Jquery code start    ?>    <script>        jQuery(function($){            var a = 'checked',                      b = 'input#ship-to-different-address-checkbox',                 c = 'input[name^="shipping_method"]',                   d = '<?php echo $local_pickup; ?>',                     e = c + ':' + a                f = 'div.woocommerce-shipping-fields,' + b;            // 1. On load: when the chosen shipping method is our defined shipping method            if( $(e).val() === d ) {                // Hide shipping fields section                $(f).hide();             }            // 2. On shipping method "change" (Live event)            $( 'form.checkout' ).on( 'change', c, function() {                // When the chosen shipping method is our defined shipping method                if( $(e).val() === d ) {                    // if the checkbox is checked, uncheck it first                    if ( $(b).prop(a) ) {                        $(b).click();                    }                    // Hide shipping fields section                    $(f).hide();                } else if ( $(e).val() !== d ) {                    // show closed shipping fields section with (unchecked checkbox)                    $(f).show();                                    }            });        });    </script>    <?php    endif;}

Code goes in functions.php file of your active child theme (or active theme). Tested and works.

Related: How to make ship to different address checked when using Free Shipping and Flat Rate?