This one?
I saw it on /u/. They think it is just a very butch female MU.
Not that I would EVER go to /u/, much less frequent it, no sir >_>
Also two comments in Moon after it. May not be related (aren't direct replies)
"幼女同士の百合会話も有るみたいね
システム的には会話だけで子供はできないんだけどね"
"マイユニ女で全女落として百合ハーレムとか野望ひろがりんぐ"
I checked /vg/'s FE thread and here are some shots (I ignored the ones alreddy here)