This a general issue that we see with our VMware shared folders and is a consequence of exporting the shares under "\\vmware-host\Shared Folders".
Windows explorer will often ask for the for the volume size attributes of this folder, which is virtual and can contain shares of multiple drives, as in this case.
I suspect your second share has less than 5.6GB free which is the issue here.
So we have a choice do we return the size of the biggest or smallest volume of the host drives the shares map to.the default setting is to return the size of the smallest drive that is mounted under the shared folders. Hence why Explorer will say out of space when there is for that particular volume.
There are two workarounds here one temporary and one more permanent.
The temporary one is to go into the virtual machine sharing settings and disable the other share and then do your copy and then go back and enable it once more.
The second one is to suspend the virtual machine and stop Fusion. Then edit the VMX file and add/change a setting for the volume size calculation on the
"\\vmware-host\Shared Folders" virtual folder from the smallest to the largest drive. When you restart Fusion and the virtual machine you should find the copy will succeed.
I don't have access to get you the setting right now but will do later today.
i will update here again later with that information.
Please let me know if this helps, at least either or both workarounds.