Check for equipped weapon

[MagicSN]

How do I check (in the code of a magic weapon) if this weapon is equipped? Best also something like I can check if it is equipped as Offhand. Is this even possible? The code for normal magic items to see if equipped seems not to work (if I insert this it behaves as if the weapon is never equipped - probably due to weapon equipment not going over the normal equip UI but over the special tab - is it possible to check the settings of the special tab for a weapon somehow?)