fiducial.
Hmm. For example, we once (some years ago) had designs panelized by JLCPCB, and they added fiducials outside the board area in the whatever-it-is-called the area of the panel between the boards. Yes, usually it’s easy to see the direction of the board, but it may be easier to automatize with fiducials.
Using 3 fiducials is recommended to make the board/panel unambiguously asymmetric.
Layer alignment target should really be obsolete, maybe except for some old obsolete processes. Nowadays layers can be aligned using coordinates. Modern factories like JLCPB or PCBWay don’t need alignment targets.