It's not real, but these cars have good odds.
The Agera RS has been the fastest verified car in the world since 2017, and would be the perfect vehicle to introduce Koenigsegg to Gran Turismo. It is also quite historic as well, having broken a land speed record held on public roads. The particular example that Polyphony would want to include would be CN.143, or "Ruthie", which had the same engine as the One:1, and was the exact same car that set the record.
The Challenger SRT Demon was last seen on the datamine, and with the lack of any modern Challenger on the car list, it's surely going to fill the gap.
With the Porsche 911 GT1-98, it's another car that can expand the Gr. 2 roster, with it being a longtail prototype-style GT1 car and the racing companion to the 911 GT1 Strassenversion that we already have in-game. And another is that it has good reason to be featured eventually as it won Le Mans during the year it raced.
As for the Mazda Autozam AZ-1, it's been a familiar Gran Turismo kei car since it was featured in GT2, and is also on the datamine. With its inclusion, the Kei "ABC" trio, or "Kei car American immigrants" will finally be complete. However, the model won't be the aforementioned Mazdaspeed variant, but rather, the familiar model that's been in the series ever since.
