Is it possible to override email templates ?

Email templates are located in /plugins/woocommerce-pretty-emails/emails/ You can edit these files in an  upgrade-safe way using overrides. Copy it into a directory within your theme named /woocommerce-pretty-emails/emails/

Example: To override the customer processing order notification, copy:  woocommerce-pretty-emails/emails/customer-processing-order.php to /yourtheme/woocommerce-pretty-emails/emails/customer-processing-order.php