Does it still strike you as odd to see Cate Blanchett or Meryl Streep described as an actor?
Actress is in fact a relatively new word in English, because no females performed on stage in England before the seventeenth century (although the OED does say that actor was applied to both sexes in the early days of the mixed stage).
Even now, not everybody is using actor for both women and men. There are more than 75,000 women who describe themselves on LinkedIn as an actress. Oscars are not yet awarded to the best female actor – much less to the best actor, regardless of sex (or gender).
Other –ess words faded away longer ago. It would be rare nowadays to ask to speak to the manageress of a shop. Even early in the twentieth century the terms poetess and sculptress fell from use because they sounded faintly derogatory (OED quotes a passage in which poetess is described as ‘somewhat outmoded’ in 1903). Waitress is disappearing – but so too is waiter, both largely displaced by server. One would still use priestess, but only in relation to a non-Christian, possibly historical religion (‘the priestess of Diana at Ephesus’), rather than for a female ordinand in the Anglican churches that have them.
If you are still using legal Latin, you may still also be referring to a testatrix, executrix or (possibly) administratrix (although Ontario’s Succession Law Reform Act uses the –tor forms for both men and women). Aviatrix is as dead as Amelia Earhart, but dominatrix is firmly entrenched (perhaps because no one would dare mess with one).
United States congressmen have been joined by congresswomen since the early twentieth century, but congresspersons or congresspeople never gained much terminological traction. (Do you remember Saturday Night Live’s send-up of The Village Persons?)
If the trend in English seems to be going towards the gender-neutral (or, actually, to the terms formerly applied only to men, like priest), continental languages have gone the other way.
In the days when there weren’t many, a female lawyer in France or Quebec used to be un avocat, just like her male counterpart; one now sees une avocate. In traditional European French, a female judge was madame le juge; madame la juge was the polite way to refer to the wife of a male judge. Quebeckers – either less polite or more egalitarian, depending on how you look at it – dropped madame la juge for the judge’s wife, and started using it for a Madam Justice.
A woman lawyer in Italy is an avvocatessa, and a female academic is a dottoressa or professoressa.
In Germany, the feminine equivalent of a Rechtsanwalt (lawyer) is a Rechtsanwältin, although the Federal Lawyers Code uses the masculine form as a ‘gender-neutral’ term. In academic circles, one is either Frau or Herr Doktor (or, if super-qualified, Herr or Frau Doktor Doktor or Professor Doktor).