If one wants to submit one's manuscript to multiple journals of a publisher (IEEE, Elsevier, Springer etc.), is it possible for a publisher to detect it? I mean if any publisher keeps a database of submitted manuscripts to crosscheck newly submitted manuscripts with the existing ones.
Surprisingly enough, they probably can't. Modern Editorial Management Systems can detect multiple submissions to the same journal, even if the previous submission was years ago, but the EMS still only works for that one journal. Inter-journal sharing does happen, but as far as I'm aware, it's not common and even then it's often only the reviewer pool. The editors of one journal cannot see which manuscripts are submitted to the other journal.
If you are detected by the publisher, the most likely reason is because one of the production staff handles both journals and noticed it. Alternatively, it's possible the editors of both journals invited the same reviewer who noticed it.