Install
This is the repository archive. It installs, but the folder name will carry the branch suffix and updates will not flow.
Install straight from GitHub with WP-CLI:
wp plugin install https://github.com/bitfade/themeforest-themes-update/archive/refs/heads/master.zipUpdates itself. It ships its own updater, so new versions appear under Dashboard → Updates.
Themeforest Themes Update WordPress Plugin
Install the plugin, then edit wp-config.php and add
// USERNAME = buyer username on Envato
define('THEMEFOREST_USERNAME','USERNAME');
// APIKEY = buyer api key
define('THEMEFOREST_APIKEY','APIKEY');