just an update that I found an answer for myself. Note: not sure if it would work for you but hopefully this helps you at least go towards the right direction. :)
After going to Toulouse's Pole emploi, prefecture, l'inspection du travail, and CPAM offices, they all did not know really anything about the visa. I talked to the Consulate of Canada in Jean Jures and she was helpful, friendly and patient. She told me that based on what she can see for the regulations and information about the work and holiday visa for Canadians in France, we CAN work remotely.
I also went to the Centre de finance publique toulouse to ask about taxes and they too were friendly, efficient and helpful. I confirmed with them that for my situation, I just pay normal taxes - I do not need to register as a self-employed person or something like that.
Not sure if this info will change so I advise you ask for your specific situation as I will double check for myself again when it's time to file taxes for 2020 in 2021. Good luck!