Credit Card Processing Fee - Pass To Customer

I am looking for options to automatically have credit card processing fees charged to the customer. 
It is legal for me to pass these fees onto my customer (In Canada) but I'm having a hard time sorting out how to do it. 

I currently use Stripe, and they don't have an option for across the board fee pass-through. 

It looks like Square has this option. I wouldn't be opposed to switching to them, but I'm curious if anyone has this set up already and uses it for school/sports volume type orders. I want to ensure that it applies to every Square transaction that comes in through Sytist, and not just transactions that I initiate in Square. 

Or, is there an option to set this up in Sytist? 

Worth noting, not all of my clients pay by credit card so just including it in all prices (as I do now) is not ideal. 

There isn't an option in Sytist to charge a credit card fee at this time. You can't through the actual processors either.

I just changed my "Tax" from 6% to 10% and that wrote a disclaimer explaining.

"You may notice tax is 10% instead of 6% and that is due to Sales Tax being 6% and CC Processing and digital methods charge 3.9%. If you have any questions please let me know."