With this filter hook, you can easily add new Templates. But you just need to place it inside `wp-content/plugins/woo-invoice/templates/invoice-templates/my-template` Each template should have minimum 3 files.

my-template.png
style.css
template.php

 

// Add New template
function add_my_template( $templates ){

    $templates['my-template'] = __( 'My Template', 'text-domain' );
    
    return $templates;
}
add_filter( 'wooin_invoice_templates_internal', 'add_my_template' );