Multiple Devices Syncing to Common Network Folder

It will probably cause some unpredictable side effects. If the need for the 2nd server is just to ensure that there is always a latest data on the network, then I’d suggest setting up a 2nd server syncing to a different folder on the same network location to satisfy that at double the space cost, and no risk of breaking things. You can later potentially invest time into setting up deduplication if your storage supports it.