Basic sort, with annoying bug
Python 3, 36 bytes

Bug-free version, 37 bytes



lambda l:sorted(l,reverse=l[-9:]==[])


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Annoying version, 36 bytes



lambda l:sorted(l,reverse=l[9:]==[])


Try it online!

This depends on the input and therefore does not qualify for the bonus.
It has a probability of around 2% to fail. It fails when the input length is lower then 10.

Combined with LyricLy's answer this gets 34 bytes:

lambda l:sorted(l)[::l[9:]&gt;[]or 1]
lambda l:sorted(l)[::l[9:]&gt;[]or-1]