It seems that LOCO Translate is working. I created the language files with LOCO Translate by saving them in the languages/plugins/woocommerce-en_US.po path.

Replaced "Collection from <strong>%s</strong>:"
with "X2_Collection from_X <strong>%s</strong>:" for testing,
or "<strong>%s</strong>:" for remove.

The "Collection from" title will be replaced in "You've got a new order" and "Order has been received" email notifications.

Tested on:
WordPress 6.8.1 (Language: en_US)
WooCommerce 9.8.3
Loco Translate 2.7.2