I'm starting to think it is. I've had a look up and down Autobahn 9 in Germany, and I can't find any junction like that (aside from its junction with Autobahn 38, but it's clearly not quite right and is also near Leipzig).
I've also had a look up and down Autobahn 9 in Switzerland and Autobahn 9 in Austria. Neither have a junction that looks like this one.
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However, I've just looked along the other road I've mentioned, namely Autobahn 14. It has a junction with Autobahn 2 near Magdeburg which looks like a good candidate...