Unsolved Non Cloud/NAS solution for syncing Recalbox saves

[retrospot]

Hello, I’m wondering is there a solution for syncing save files between multiple Recalbox instances on the same network.

Ideally the solution for me would not be any of the following because files are stored locally on each device:
NAS
Cloud service

The ideal solution would be able to manually or automatically copy the latest save state / save games from the current device to other Recalbox instances on the same network by having the instances powered on at the same time.

Bonus points for optionally syncing roms that don’t exist on the other devices

Does anything like this exist?

Thank you