The Bavli, M'gila 14 amud 1, quotes:
Forty-eight prophets and seven prophetesses prophesied for the Jews….
Further along on the page, it questions this:
Were there no more? But it says [in I Sh'muel 1:1] "there was one man from Ramasayim Tzofim", i.e., one of masayim, two hundred, tzofim, seers, who prophesied for the Jews!
And it answers:
There were more. Indeed, the rabbis taught "There were so many prophets for the Jews — twice the number of people who left Egypt [at the Exodus]. But a prophecy needed for posterity was written, and one not needed [for posterity] was not written".
Thus, forty-eight prophets and seven prophetesses prophesied for the Jews and have their messages included in Tanach; many more prophets prophesied for the Jews and do not have their messages included in Tanach.
My question is: Were there prophetesses with messages for the Jews, beyond the seven whose messages were for posterity? Any sources that indicate one way or the other?
(I do not think the answer can be found in D'varim Raba (7:8), which quotes Rabbi Hoshia:
The least [person] in the days of Moshe saw what Yechezkel, a great one among the prophets, did not see — [these were] people with whom the divine immanence spoke face to face, as it says [in D'varim 5:4] "face to face God spoke with you…".
These people — presumably women included — had prophecy, but, unless you can support such a claim, I have no reason to think that it was of the sort that included a message for the Jews, which is what M'gila is discussing ("for the Jews"). I'm asking about message-for-the-Jews prophecy: did women, beyond the seven listed, have that?)