I dabble in figure collecting, so I've seen (and owned) a few bootlegs. Some are definitely harder to tell than others. But one of my favorites is a bootleg series of the Attack on Titan Nendoroids.
For those who are not aware - Nendoroids are basically a figure line of chibi-fied versions of whatever character. The line is done by a few specific companies (usually Good Smile Company, but there are others) They come with swappable arms, legs, faces and usually have some neat accessories.
For reference, here's what the official merchandise looks like.
Aaaand then we have these things...
...I think it speaks for itself.
I kind of find the bootlegs fascinatingly bad.
I also have a bootleg NES multicart. It was grandmother's originally and contained '700' games. (Many many many of them were repeats with slight graphical changes.) She apparently picked it up at a flea market a long while back when she was in Quebec. Interesting what you can find at those, ha ha.