Download the plugin below:
http://cl.ly/3L381J3O0T22/download/event-espresso-enable-all-countries.zip
Login to your WordPress dashboard (WP-admin) and go to Plugins. Next, click on Add New --> Upload and browse to the plugin on your computer. Then select the zip file and begin the upload process. Wait for the plugin to upload and then click on Activate.
You can then deactivate the plugin and delete it from your site.
References:
http://eventespresso.com/topic/adding-all-countries-in-dropdown-list/
https://eventespresso.com/topic/how-to-add-missing-countries-and-how-to-enable-all-countries-at-ones/
http://eventespresso.com/topic/adding-countries-to-dropdown-menus-for-registration-without-changing-currency/
http://eventespresso.com/topic/show-all-countries/
https://eventespresso.com/topic/is-adding-countries-mandatory/
https://eventespresso.com/topic/paypal-pro-international-countries/
https://eventespresso.com/topic/country-drop-down-and-numeric-only-text-field/
http://eventespresso.com/topic/fast-way-to-add-country-dropdown-field-to-registration-form/
http://eventespresso.com/topic/country-state-what-is-the-expected-process/
https://eventespresso.com/topic/adding-and-editing-countries/
Check out more improvements for Event Espresso