Steel Pull-Thru Rivets can surface flush on both sides.
13 Types of Rivets + Applications & Working Principle | Linquip
Flush mount blind rivet nut
STEEL COUNTERSUNK RIVET 1/8 X 1/4
Flush Riveting Tips - Glasair Aircraft Owners Association
Riveting the Left Elevator Skin – Lynn's RV-7 Build
Comparative Tests of the Strength and Tightness of Commercial Flush Rivets of One Type and NACA Flush Rivets in Machine-Countersunk and Counterpunched Joints - Page 9 of 16 - UNT Digital Library