Offsite backup with rsync?

Hi all,

Me and a friend want to create an offsite backup to another house, following the rule of 2+1 backups.

I have done some research and came up that rsync might be the easiest way to accomplish this need, plus is included in every Linux flavour (he's on a Synology).
Honestly I don't trust Duplicati since I've experienced a ton of reliability issues.

The idea is to make the initial sync offline, then plug the drives in the new NAS and sync every week the differences.

Does this make sense? Can rsync be used over the internet, and are there any security considerations to be considered?

lol I actually forgot I made this lonely post.

I figured out that Rsync is not the ideal candidate.

I played a lot with Borgbackuup which is perfect for this purpose, then wrote extensive guide here.

The main pre-requisite is setting up SSH key authentication, then everything else is covered in the guide. I've done a lot of testing and Borg is solid and reliable, will go "in production" during the Christmas holidays.