If you apply for sponsorship inland while your status is illegal because of your overstay, they will not kick you out but it will complicate your case so instead of getting your open work permit in 6 months, they may require an interview making you wait a year or longer and during this time, you must stay in Canada because that is the requirement to apply inland.
If you apply outland, it doesn't really matter where you are. You can be in the US or in Canada but you must keep your status legal.
Getting a work permit while you are in Canada illegally is also pretty much out of the question. Work permits are granted to people based on the belief that they will respect their expiry and leave if their work permit is not extended. If you overstay a visit visa, how will you convince them that you will respect the boundaries of your work permit?
If you have overstayed less than 3 months, you can still apply for restoration of status.