Can I sync folders in two devices over Bluetooth?

Can I sync folders and files in two Android devices? These devices are physically nearby, but not connected to the same Wi-Fi network. They are connected to the internet using their respective mobile data connection. Maybe there's a possibility using e.g. Bluetooth and maybe use Wi-Fi Direct when large data transfer is needed? I dont want AirDrop or NearbyShare like functionality. It is rather like Resillo or Syncthing over bluetooth.