I believe the privacy will be set to whatever it was on the journal you're importing from, unless your default setting here is stronger. ie, if your default here is public, the privacy will be set exactly how it is on the other site; if your default is locked, it'll all be locked and/or private; and if your default is private, it'll all be private. You should be able to change your default to private here, then import your other journal, then set it back - that's what I did.