Welcome to Android Central! It looks like they're all confusing the Galaxy A42 5G with the M42 5G (which does have the flash at the bottom edge of the stovetop). This is puzzling -- not sure why they would make such a broad mistake. It doesn't look like there are any regional variations for the A42 5G. Let me look a little more ...
EDIT: I found one, but this still doesn't explain such a major discrepancy.
https://smile.amazon.com/LEEGU-Prot...y+a42+5g+case+3+camera&qid=1625710861&sr=8-15
A lot of reviews of the phone show a quad-camera setup with the offset flash, but the official Samsung site shows the 3 rear-camera setup (and the Best Buy listing also shows that).