Through check-in is only available at PVG from LX, LH, and VS flights to NZ service or vice versa, which is why the transit counter is not attended most of the time, as NZ only have 3 weekly flights (soon 4 weekly). Between other airlines you will have to clear immigration, pick up bags and re check-in on the departure floor.
I look at this as an experimental service initiated by NZ or *A which could lead to full reciprocity among all *A carriers serving PVG in the future. However FM having left *A is not helping.