When you link your devices, you can choose how Sync will be treating added folders. There are three synchronizations modes available: Disconnected, Selective Sync and Synced.
Read also: Can I connect two pre-populated folders?
When Selective Sync or Synced modes are enabled, Sync will be putting all new folders into the default folder. However, if you want to set the location of a synced folder manually, you should switch the synchronization mode (on the device where custom location for new folders is to be chosen) into ‘Disconnected’:
Click 'My Devices':
Choose 'This device’ > ‘Disconnected’:
Now if you add a folder on your other device, on this device it'll also be displayed in the Sync interface, however, no synchronization will start until you hit 'Connect':
To connect the folder and pick custom location for it,
- hit 'Connect'
- In the next window show the path:
From now on, all new folders added on your other linked devices will be synced to this device in Disconnected mode. And every time you will be clicking 'Connect' you'll be able to choose a custom folder location.