If she already has a flight booked that would be excellent evidence that she is only visiting you. Also depends on what belongings you are moving to Canada. If CBSA sees a household of both your belongings that may be a concern for them. Some have had the PR move on their own. Nobody can predict what will happen at the border but would make sure you don't state that your spouse is moving to Canada although it will be pretty clear that she is.
Just wanted to update what I heard from the CBSA helpline. I called them twice to see how different officers might react to the scenario. I explained my situation that I am PR but my wife has a visitor visa and she will be in the same car with me, is that a problem? Both officers said the same thing that it is not a problem as long as she can prove that she is an immediate family member(spouse in this case).
The first officer gave a list of things my wife has to carry/declare while she is at the border, which we kind of know already:
1. Negative Covid test result
2. Proof of relationship with me(Marriage Certificate)(She will carry the last 2 years of rental lease agreements as well where both of us are there)
3. Copy of my PR card
4. At least 15 days of stay she has to mention(Quarantine plan)
The second officer went into more details about my PR. He asked me all the details about when did I become PR, when is it expiring. I think he was assessing if I know the PR terms. When I asked him about my wife travelling with me on a visitor visa in the same car, he was not concerned. He also said the same things the first officer said that negative Covid result, marriage certificate, my PR copy etc is required. He even went on to say that once your spouse is talking to an officer, she can mention that she is
moving with you and officer can give her visitor record which will allow her to stay more than 6 months while I apply for her PR/work permit. I did not ask this question but he explained this to me in a very nice way. It feels as if this was a very normal case for them. I asked again that but on visitor visa you can only stay a max of 6 months in one go but he again said that you will have to apply for inland sponsorship so you will need extended stay for your wife.
I know things can be different once we are at the border but talking to the border officers made me feel a little relaxed.