What job she has now is irrelevant. All that matters is how IRCC will assess the spent conviction against Canadian criminal law.
This is a complex / unique question and I certainly can't answer it. I think it's highly unlikely you are going to get a definitive answer on this forum. I think your friend should get a consultation with a good Canadian immigration lawyer. If your friend does not have the funds for a consultation, then she'll just need to make the decision herself on whether she rolls the dice, tries coming to Canada, and sees what happens.
I can't comment on working as a lawyer in Canada. Criminal convictions are obviously a problem. I don't know how they look at spent convictions and whether this will be a bar to entering that occupation. Suggest checking with the Canadian Bar Association or someone similar like that. This part of your question isn't immigration related.
Right, thank you so much for your time!