Not likely. The fleet is used in passenger service until the 777-9 is available. Some parked aircraft might be just needed as part donors and not too many might be left for conversion.
AFAIK the passenger version has light weight, custom configured floor beams, not sure how this would work with main deck cargo? Plus nobody has upper deck cargo loaders.
I'd speculate the 777-300ER will be converted instead. Huge numbers will come back from leases. Perfect for package cargo and Amazon.