On Premise File Server for Remote Sync

Can OwnCloud be used to sync files on itself with remote users?

I have a file server at 'Site A' with a couple desktop clients. I have another location 'Site B' which currently accesses 'Site A' via VPN.

Can I install Owncloud on the server at 'Site A' while the desktop clients connect to the file server via SMB and have 'Site B' connect via the OwnCloud desktop app?

Considering I have three computers on 'Site A' I would prefer not to have the data duplicated 3x at the same physical location, so syncing within the file server is preferable.

Thank you.

Yes. That works and is one of the ways we recommend to solve this.