Synchronize Data between two locations

I have to locations with a lot of data. Both locations have a slow Internet connection. So it's impossible to sync the Data between both locations via Internet. So the idea is to use a sneaker net to sync the Data. When I'm at location A, I will plug a NVME Drive into a Server. When I'm leaving I will take the drive with me. And when I'm in location B, I will plug the drive into the other server. So what is the best way to sync the data? I found the Project Sneakersync: https://github.com/lamyj/sneakersync But this Project does not work for me, because of some missing limitations: 1) In the beginning I have about 45TB of Data to sync. But an limited amount of time and Space on the NVME. 2) The Sync has to work in both ways. From Server A => B and from Server B => A.