Translation:I do not have brown clothing besides my shoes.
In English, "other than," "besides," and "except for" are often interchangeable, too. Those seem to be the closest direct translations, but even so there are others that serve the same purpose: "aside from" comes to mind.
I would suggest to Duo that if words or phrases are interchangeable in the target language, then the allowed translations should permit that. If they are NOT interchangeable in the language we're learning, then we should be given lessons on when to choose one over the other.