Copy from a read only workspace to a read/write workspace is not available.

Hello
I have 2 workspace relying on 2 different storage. For some users the first workspace is read/only and the second one is accessible in read/write. Copying a file from the read only workspace to the read/write one is not possible ( only possible to download from the first workspace and then upload the file in the second one).

Is it an expected behavior ? if yes why ?

Thanks in advance