This may or may not be true (and the docs on the community / support site are thin on this info) but it seems that to have access to "Move Assets between workspaces" you need to be an Admin role? This seems strange as moving folders/assets is a fairly simple run on the mill marketing task?
You need the Workspace Administration role that has an option to "Move assets between Workspaces", it should be the very last permission in a role configuration.
You need the Workspace Administration role that has an option to "Move assets between Workspaces", it should be the very last permission in a role configuration.