I know of 4 different transforms that swap 2 edges and 2 corners.
LD'BRDR'B2LBL2D    (FD,RD),((DLF,DFR)
R'DRD2R'L'DRD'LD2      (FD,LD),(FDL,FRD)
FD2F'B'DFD'BD2F'D       (FD,LD),(LFD,BDR)
FLFL'UBLB'U2FUF     (FD,DL),(DLF,DFR)

I found the first 3 of these before I saw Singmaster and modified one of
Singmaster's into the fourth one which he didn't even have recorded.