First clue is "Female Ninja." These are the female ninja that we don't yet have in the game but that do exist, according to KonohaProxy:

Temari [Christmas] (Wrong time of year)

Kurenai [Summer Clothing] (Wrong time of year, also literally just came out in CN)

Shizune [New Year] (Wrong time of year)

Ajisai (Does not satisfy the second condition)

Karui (Does not satisfy the second condiiton)

Thus, this season's ninja is either an old ninja or a ninja that even CN doesn't have, which is very unlikely. Of course, it's also possible that I'm overlooking a ninja because KP doesn't have them tagged properly.