@erikture
There are a few alternatives, but only 3 that works with FTP.
best is, with these you don't need to sync once uploaded via FTP.
MMM File List
Very simple with super suport
https://wordpress.org/plugins/mmm-file-list/
FileAway
Not so simple, but with more features.
Confusing to configure at first, but once you have it working, its great!
https://wordpress.org/plugins/file-away/
CIP4
Super simple. Not much updates, but probably because it is so simple, it doesn't need any.
https://github.com/wp-plugins/cip4-folder-download-widget/commits/master