I'm not at all familiar with that breed but looking online they have a fascinating history. Some people believe them to be the foundation stock of the Polish breed. My understanding is that they are pretty small, come in different colors/patterns, have a Vee shaped comb, a flattened crest, and feathers on the legs.
I don't know the genetics of their Vee comb, whether the Vee part of that is dominant or recessive so I trust you on that.
The crest and the feathered legs should be dominant, though because the Barred Rock does not have those genetics they may not be as impressive as on your Pavlovskaya. Still, expect to see a crest and feathers on the legs.
If your Pavlovskaya are not barred you can possibly have another interesting effect from that cross. The barred gene is sex linked, which means that the hen gives it to her sons but not her daughters. So any males hatched form that dross will be barred since barring is a dominant trait. Any females will not be barred as long as the rooster is not barred. If the offspring is white you will not see the barring but it will be there. Depending on down colors/patterns you may be able to see a light spot on the head of the males that won't be there on female chicks when they hatch.
Thanks for posting, I'd never heard of that breed before. And welcome to the forum.