With out of province/country plates you won't have a problem without winter tires in terms of law enforcement. For sure, winter tires will be nice in poor weather but I have found (I grew up in Quebec and return often) that Quebec highways are kept in excellent condition. Driving will be bad during storms but otherwise roads will be clear and clean and crews get out very quickly.

I couldn't figure out whether or not chains were legal in Quebec. I've never seen them on a vehicle there so they are certainly uncommon. None of the highways you will be on require that kind of traction as they are mostly flat or have gentle grades (even in the mountains).