My first thought, regardless of whether I can ‘do’ a plugged coin or not, was whether it was genuine? A lot of fake coins are scuffed up to look old, and the scratches in this piece look so intentional and even, on a coin I would’ve expected to be buckled (or wavy at best) from such a harsh life, yet it has such a perfect and even wear to the raised surfaces?
Here’s an example of some of the copies out there for these groats? I’m not claiming yours is counterfeit, just saying this one pricks my suspicion enough that I wouldn’t personally want to buy such an example blind!
There’s a really good Elizabeth I fake shilling out there, that was even cast with a plug in place. Either they hadn’t noticed the original coin was plugged, or they thought it might avoid the scrutiny of serious collectors, on account of the market they are typically absorbed by? Who knows?