Not sure if you quite understand how this works.
It is not illegal in any civilized country, even the US, to purchase someone's time and companionship. So communicating with an escort and buying an hour of her time is not illegal.
Soliciting sex for money is illegal. In the U.S., it is illegal to solicit sex for money and illegal to offer sex for money. In Canada it is only illegal to solicit sex for money. So any email or verbal communication with an escort should not mention any sex act. It is of course okay to mention money, since you are buying a block of time.
You are not guaranteed that any sex will occur during the time you purchase. If the escort you see has reviews, and those reviews reveal what sex acts she typically chooses to perform during the hour, you have a good idea as to what might happen. If you want to be extra safe, don't mention her reviews in the email or text you send to her.
For there to be an arrest regarding an email or phone call, you would need to be communicating with a police officer. So don't communicate via email with someone off of backpage or annonce123 with no reviews, if you want to be certain that you are not communicating with the police.
Even when you are communicating with a known, reviewed escort, just don't mention sex acts. But for there to be an arrest if you do mention sex acts, the police would have to seize her (or her agency's) emails or phone, connect you to that email address, and prove you sent the email. Same with telephone conversations, which would have to be recorded. There have been no arrests for this, because only in a world of complete paranoia, could that ever happen.