What is the passive voice of the following sentence:
Has anybody done all the work?
Could you please explain in detail how this is done?
There are two main possibilities, depending on context.
If the question is addressed to (for example) a classroom, and the point is to find out whether some people have yet finished an exercise while some might still be working, then the passive (and very ugly) form would be
Has all of the work been done [or completed] by anyone?
In this situation a much less awkward approach would be to stick with the active form of your original example.
If the focus is, instead, a certain task or project, and it doesn't matter who might have done the work so long as someone has finished it, the (again unnecessarily) passive question would most neatly simplify into
Has all of the work been done?
The point at stake here is simply whether or not the task has been completed, and the questioner does is not especially concerned about how that was achieved, or by whom.
Strictly speaking, there isn't any passive form of a question, though you can question the passive form of a sentence. And there isn't any passive form of a perfect aspect, though you can put the passive of a sentence into the perfect aspect.
Suppose I use this notation for the question form of a sentence: Q(sentence), and this for the present perfect aspect of a sentence: Perfect(sentence). Then I could write the declarative form of your example "Has anybody done all the work?" as Q(Perfect(somebody do all the work)). Although Q has no passive form, and Perfect has no passive form, I can find a sort of answer to your question by passivizing the embedded declarative "somebody do all the work", which gives:
Q(Perfect(all the work be done by somebody))
The present perfect of "all the work be done by somebody" is "all the work has been done by somebody", so this leads us to
Q(all the work has been done by somebody)
In the question form of a declarative, "some" is replaced by "any", and the subject is inverted in order with the tensed auxiliary, so we wind up with:
Has all the work been done by anybody?