I need some clarification. If I understand correctly, you can cast Misdirection as yourself or another person as the subject.
So a caster can choose to his friend as the subject and something else as the object whose auras he will assume. Correct?
Also, can the "object" of Misdirection be a person as opposed to a thing? Can the caster assume the aura of someone else whether that person is a non-magic user, arcane or divine spellcaster? Or that someone else (the subject) appears like the caster (the object)?
Lastly, Arcane Sight is all based around auras. Not only does it allow some to know location and power of all magical auras, it allows the person to even determine whether a creature has any spellcasting or spell-like abilities, whether these are arcane or divine, and the strength of the most powerful spell or spell-like ability the creature currently has available for use.
So is it possible to fool the person with arcane sight that someone else (say a non-spellcaster) shows the same aura as the caster of Misdirection?
I think the answer is "yes" for all the questions except whether Misdirection can fool the "determine whether it has any spellcasting or spell-like abilities, whether these are arcane or divine, etc" bit of Arcane Sight.