given the YHZ origin, probably best just to put them on Air Canada in C via YYZ.
Only one stop, full flat beds on the YYZ-PVG leg and no back tracking. Service not nearly as good as on Asian carriers but very comfortable and much much more convenient than any of the true F options which would all involve 2+ stops, immigration etc.
Any of the LX/LH F options from YYZ/YUL would take much longer, involve an additional stop and cost far more...