If the ID is 8.2, they are not ABEC-5 bearings, they are trash.
The problem with Amazon and I assume eBay is that the sellers are extremely price competitive, and they outright lie.
I bought some bearings on Amazon that were said to be sealed, yet they obviously were not.
These also had a bit of a crunchy feel to them but I can’t measure it or prove it.
Here’s a table I found that says that the inside bore for ABEC-5 bearings are allowed to be 5 microns undersize and they are not allowed to be oversize.
https://www.astbearings.com/bearing-tolerances-precision-levels.html