Hi @Phoenix85 ,
The error seems to be correct - as shown in your first screenshot the "local" storage is not configured to accept content type "Disk Image", which is what the Virtual Disks are called in PVE.
OP's issue is "working" storage. As the message says - during the import the space is needed on working storage. And OP's working storage is set to "source". I have a suspicion that "Working" storage for File import needs to be File-based - as stated in the error message.