Station wagon full of tapes.

Rsync

LAN party!! You have the optimal excuse to make one happen ;)

We use Tailscale to share between accounts.

But for large transfers I use an encrypted HDD.

You can’t beat the bandwidth and reliabilty of mailed ssd’s

For large volumes of data, nothing beats shipping a large external drive (with a fast interface) from location to location.

If you’re wanting to share all files, many of the methods already mentioned work well. If you’re wanting to share specific files, CopyParty is a good way to go.

Surprised no one just said Samba or NFS over a tunnel (Tailscale, WireGuard, etc).

Or by “sharing” do you mean keeping files synced between the two for replication?

SFTP or WebDAV would work.