Augsburg 1 Pfennig 1780 error

It looks like a combination between https://en.numista.com/catalogue/pieces97975.html and https://en.numista.com/catalogue/pieces48255.html , what do you say about it? Error?

It looks like you're right. I didn't find this variety in Krause nor anywhere online though I didn't do a systematic search. I hope a specialist of German coins will give his/her opinion on this.

If you're right, it would then be a mule, i.e the combination of the obverse of one issue with the reverse of another. So, you could try finding more examples online using the technical German word for mule + 1780, e.g. in Google Images.

In German language we call that:
Zwitter Taler, Zwitter Pfennig...

Thanks apuking.

Here we happen to have the two varieties side by side, and both seem somewhat common given the price, so I don't think it's a mule.

Indeed the same one in the link, Unfortunatelly I don't think I have the forster catalogue but Im not sure they played the correct catalogue number.
3 other examples with Forster 688 all link to this coin https://en.numista.com/catalogue/pieces48255.html

There are plenty of pfennig coins with sometimes just minor differences, some do not have own catalogue numbers, especially Krause is missing some varieties. Still if not in absolute perfect condition they usually do not fetch high prices.

So this one is not a mule, but a variety which is not on numista yet, right?

One way to go about this is to search by Forster catalogue numbers in Google:

Forster 689

Forster 690

Forster 687 (2 Pf.)

Forster 691 (1 H.)

So, I wouldn't yet rule out a mule because, as apuking pointed out, MAShops' Forster 688 seems to be a wrong catalogue number.