I received a provincial nomination last year and applied for PR but I am still waiting on a response and my current work permit is good for two more years. Am I allowed to work remotely for my current Canadian employer if I leave the country for 6 months? Will this affect my PR application or my work permit validity?
Yes, if:
You're nominated under a PNP program, then you are expected to permanently reside in the geographical boundaries of the province during the processing of your PR application. This is common sense (and listed as a condition in your certificate and closed work permit) and I'm not sure why people keep asking - the point of PNP is to bring you in the province, contribute taxes to province and get you to spend your money in the province. You're not allowed to pick and choose what you want to do because it's more convenient or better for you. The PNP deal is that you live and work in the province that nominated you. If you choose to work remotely for excessive periods of time IRCC and/or the provincial immigration anti-fraud unit will discover it eventually and cancel your application because you're a non-genuine nominee.
The exception to this is where your employer is directing you to work overseas, but IRCC doesn't provide clear guidance on how this work.
If CEC then different story - as long as you fulfilled 1 year of work in Canada and have a valid permit you can do whatever you want.