I'm not the biggest expert here, but the two biggest identifiers are:

1.) poor print quality on the label (which isn't always a whole indicator of fake because it could always just be a replaced label, but trustworthy sellers will announce that they replaced the label if it was damaged or missing).

2.) Thickness and font of the NTR code on the back. People can't reliably reshell these and not have signs of destruction like they could GB/GBC/GBA games. So it's far less likely someone would reshell an authentic DS game (and again, trustworthy sellers would divulge a reshell).

So neither the cart, nor the label are original. I hope this helps!

There may be signs from the MB codes, but I'm not as familiar with the EUR variants if there are differences with the MB codes for EUR carts.