I want to hide or remove VAT (tax) line from WooCommerce order emails. Result comes out from this function "get_order_item_totals()". Already I can hide tax label from emails by using following code.

function sv_change_email_tax_label( $label ) {
    $label = '';
    return $label;
}
add_filter( 'woocommerce_countries_tax_or_vat', 'sv_change_email_tax_label'       );

I want to hide the entire row of VAT from order emails.

Depending on the status of the order, you'll need to edit the relevant email template.

For eg: If you have COD payment method enabled and the customer selected that option, the order status will be "Processing", in that case you need to edit customer-processing-order.php template.

//find this line and after it add the following line of code
foreach ( $totals as $total ) {  

    //ensure to change "VAT" with the label that appears on your email
    if( strstr( $total['label'], "VAT" ) )  continue;

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