I have seen fake chips that simply don't work. They look the part (well, often not laser-engraved but silk-screened instead), but between the heat spreader (different kind of metal too) and the LGA PCB (interposer?) there is no actual silicon inside. And then there are falsified specs, so they get a low-end CPU, remove the heat spreader, and put on the heat spreader from a real (but broken) high-end CPU. Now the package looks like a high-end one but actually is just a low-end chip and works (And is reported as such).
What I personally haven't seen yet (but might be funny) is a fake BIOS or UEFI stack that falsifies the setup screen CPU readout and fakes the ACPI tables or DMI data. Doesn't prevent the OS from using the MSR of course.
On one hand you can also get totally fine fakes, i.e. the 'third shift' runs where the silicon and packaging is all the same, done on the same production lines with the same parameters, except the package doesn't get officially branded. It essentially means the production company can create a batch for themselves at cost, and make a huge profit even when sold for half the retail price.
On the other hand, that's more effort than most scammers are willing to put in. Changing labels is the easiest. Sending a clay brick is even easier, but the scam can go on longer if you can pretend to be resolving "oops, sent the wrong CPU". Same as with USB drives that are configured to fake the NAND or HDD size. Even the external HDDs that internally contain a USB mass storage device and a couple of hot-glued metal washers was apparently lucrative. Maybe the cost of labour and materials is super low and you can afford to setup a 'fake production line' that does everything except use the actual storage device that matches the specs... And stretching the time you can keep a fake brand running, that's where all the scams have been looking for improvement, essentially a ROI calculation.
At the end of the day, if people want to get into it (fakes/scams/marketing/brand trust) it makes wording and semantics very important since people tend to have different ideas of what a fake or scam product entails.