Unless you are also using males don’t use the word females (and vice versa). That is what I would recommend to not seem too disrespectful, even then be careful to avoid being dehumanizing.

I personally tend to use variations of (fe)male identifying people. But I rarely talk about people of the same gender at all ages. That seems like something that isn’t that common though. If that is your justification for using the words females/males just be sure not to use it in other contexts.