As anyone who has worked with WooCommerce knows, the text in the system emails don’t suit every circumstance of every seller. The email text customiser for WooCommerce plugin enables you to rewrite text. There are other ways, but they are more technically challenging, involving language strings and changing template files.
The WordPress repository page for the plugin says that the plugin hasn’t been updated for the past several versions of WooCommerce. The author is Maeve Lander who works at Automattic with the WordPress.com VIP team, helping clients run WordPress at enterprise scale, as you can read on her site.
Note the spelling of customizer, which I have retained because it is the actual name in the WordPress repository. In my native British English is would be spelled customiser, with an s rather than a z.