This is a loose précis except the intro in bold which is direct translation;
"A woman from Cantille thought she was getting a bargain when she bought a bag on Vinted but the transaction did no go as she expected."
Our French customer buys a supposed Louis Vuiton bag for 416 euros but when it arrives she quickly realises it's fake. The seller doesn't want to know.
She confirmed via Vuiton that the bag was fake. Things could have ended there if the seller had accepted the return & given her a refund, except the purchaser received only threats in response.
The exchanges between the two parties quickly took an unexpected turn. The police were notified & an investigation opened. It's true that the latest messages are spine-chilling. They comprise images of guns alongside threatening messages, notably; "I know where you live..". The purchaser couldn't sleep & jumped with fright whenever anyone rang her doorbell.
«Vinted»,on their part, have for a week made no progress in the case despite the guarantees that the firm is supposed to offer for the payment transactions it controls. As for the Post Office, they could only identify the region from which the parcel was sent - Occitane & nothing more.
The seller continued his bullying. He demanded that the Vinted block on his account resulting from the purchaser's complaint be lifted. One message comprised a photo of an assault rifle [their words for the same image posted by the OP] & the following comment; "I promise that your family won't get through the weekend". Another message followed: "I have your address. You won't get a chance to speak".
[Other French media reports suggest that this is a regular scam on Francophone Vinted, or at least was a couple of years ago.]