To specify the Layer 2 path for traceroute packets, use the trace-l2 command.
F4# trace-l2 ? Possible completions: show show L2 topology vlan trace VLAN F4# trace-l2 vlan ? Possible completions: 1-4090vlan number F4# trace-l2 vlan 1 ? Possible completions: A.B.C.Ddestination IP address ASCII string destination host name HHHH.HHHH.HHHHdestination MAC address | <cr>