As with everything else in life, YMMV and much depends on your approach. Approach it as you would with any fantasy that isn't part of a "typical" session.
If it's part of your fantasy just letting loose verbally with words that are not acceptable in civilian/vanilla sex life then you will find many providers very accommodating. After all, they are in the business of "doing the things the SO won't" and many of them love that aspect of their job.
Just let the girl know what your fantasy entails first is all. If you just bust out with derogatory and "offensive" remarks she may mistake you for a different type of client that enjoys berating women and may then react less than positively. If you approach it correctly though you'll find her to be receptive and even enthusiastic which will heighten the experience for you.
As a cultured modern male part of the reason I hobby to begin with is because it can be quite liberating to throw decorum to the wind. Just give her a heads up first