https://wordpress.org/plugins/easy-theme-and-plugin-upgrades/
Allows you to upload the latest zip file of existing plugin on your site. (no more folder already exists issues)
- While upgrading, a backup copy of the old theme or plugin is first created.
- This allows you to install the old version in case of problems with the new version.
- Don't forget to delete the backup from your media manager.
easy-theme-and-plugin-upgrades