Leave the names italicized, adding in parentheses a loose translation:

Leck o mio (What world!/Can you believe it?)
Allmächt (Heavens/Saints above!)

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Note added at 35 mins (2019-07-12 09:16:16 GMT)
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Sorry, that should be What in the world? or What a world!

You cannot score any marks in an exam with a blank answer.

The first expression can of course be rendered with a '

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Note added at 1 hr (2019-07-12 10:15:49 GMT)
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with a 'more literal kiss my ...' expression,

As already pointed out by other colleagues, these expressions of surprise cannot be translated without loss of the cultural meaning. I would therefore suggest to either omit these two expression because many people from abroad will probably not know enough about the regions in Germany to understand the cultural references anyway or if the client insists on a translation, I would transcreate the content with reference that can be more easily understood. However, the only thing I can think of at the moment, which is also related to Christmas markets, is: Upper Bavaria or Central Franconia, friends’ of the Bavarian sausage (Weißwurst) or the Franconian Sausage ... who has more passionate?

I don't know if the author of the ST was intending to limit the competitions to locals from Franconia and Bavarian only. I visited the Nuremberg Christmas market quite often and I know that the visitors on the Christmas market are actually a pretty international crowd (Asians, French, ...), not only locals from Franconia. I think that in Upper Bavaria (Munich), the crowd will probably also include people from many different countries. My suggestion (friends' or maybe sausage lovers) could also include these international visitor who come to the markets.

Sadly, I think that my suggestion cannot establish the link between the word passion and the expressions of surprise that were probably intended to convey this kind of passion in the two regions. Anyway, I hope it still gives some food for thought.