Using raspberry pi as a backup drive

Joulinar extactly what I want to do but that drive is on seedbox io (not promoting) so I cannot nfs or samba on that.
is there a possiblity to :-
A - let raspberry pi check this sftp server automaticlly (I can setup username and password)
b - download new files if there are any

Example of such tool that exist is rclone which allows you to sync files but has to run manally on pi