well...here is a iron clad answer for the OP and why all dwarves have beards..
Turbine does not license the hobbit/lotr IP from CT/Tolkien Estates...they got it from M.E. Enterprises/Saul Zaentz Company.
Turbine has to answer to them about lore...they told Turbine what can be bent...and what cannot.
SZC said no gender selection at creation and no beardless dwarves.
End Of Story.