M stands for male, F stands for female. The three letters before gender stand for speaker ID.
src: 01c F
01ca010y.wv1.wav
trg: pseudo
src x trg:
+content_consist M
01cxpseudo_18.wav
+content_consist+emb_consist M
src: 00c M
00cc0714.wv1.wav
+content_consist F
00cxpseudo_4.wav