Hi. So, there is this Rarity that I got from either a charity shop (British equivalent of a thrift store) or a Facebook Marketplace bundle. It was a few years ago, so I don't actually remember which. But point is, it was a source that did not specify her line, but sold her as just a generic Rarity.
It is a large but obviously very cheap (e.g. poor eye paint quality) pony, intended for mane styling. The cheapness would line up with her being from Asda, because ASDA is a grocery store, not a toy store.
At her bottom, one can see that she is legit, because it says '©2016 Hasbro'. It also says 'HTI Toys', though.
She is nowhere within the MLP merch database.
And I could only find 2 listings of her on Ebay, and both are in Australia, and claim her to be from 'UK ASDA'. Now, this lines up, as I also found mine in the UK. But, question is, why would there only be Australian listings of her?
Strange, strange. But she has to be legit, right? Hasbro would presumably sue a product for feigning a Hasbro copyright?