FYI: T120867: Large amounts of unwanted files (mostly copyvios) uploaded via cross-wiki upload tool (A/B test of different upload interfaces) is the related task regarding excessive copyvios from cross-wiki uploads
By "disable", do you mean that the feature should be disabled entirely ($wgForeignUploadTargets = ), or that the files should be uploaded locally to zh.wp instead of Commons? ($wgForeignUploadTargets = [ 'local' ])?
Configuration change deployed.
While testing, I noticed that an incorrect error message is displayed for users who do not have the permission to upload files ("You must be logged in to upload files.", even if the user is logged in). I'll submit a fix for this, it should be deployed later this week per the usual schedule.