I've been looking at 2016 through 2018 (advertised) OEM wheel pictures on ebay. The design seems the same as my 2019's, but my 2019's have even more text-information cast into the wheels. "China" is something I'm not seeing on many OEM Gen4 wheels, plus a long identification number. ASAHI TEC seems to be the casting company. ------ From ebay, for example, is another OEM wheel - advertised for 2016 - 2018, and it does not have the ASAHITEC, nor the 005048/2015 ID number. In fact, with a few different symbols on it, I would venture a guess that it was poured in an entirely different casting company's location. That my 2019 has a 005048/2015 suggests that possibly at least two different casting companies have been producing OEM Prius wheels for Gen4's since 2015.
There are different wheels on different Trim versions. We know there is a mixture of tire manufacturers on Gen 4. The change in Trim naming makes it more difficult to compare 2019 with 2016 - 2018.
I'm still writing about the same design here. See the wheel pictured? That's the design. Not one of the other ones. Yes, of course some of the other trims use another wheel design - most use this one.
The parts diagram usually shows the different "distinguishing marks" you can find on the wheels from different suppliers Toyota has used.
Manufacturers often source wheels, tyres, dampers - etc etc from different suppliers. This is mine. May 2016:
Looks just like mine, where-as nearly all of the used 2016-2019's I've seen for sale on ebay (again, Prodigyplace - of this style) don't have the ASAHITEC and 5048/2015.
I have a set of each of the 15” Chinese and Japanese wheels. The China wheels are about one pound heavier. The same plastic wheels covers work on both styles. I haven’t seen center caps.