this usually happens automatically if you apply enough stress-relief force. In a few cases it is a good idea to give the spokes a set (e.g. using your thumbs when the spokes are near full tension ) to improve the spoke line before you stress-relieve.
If the stress-relief force is high enough (higher than most folk ever manage, and repeated), you can correct for an over-length elbow bend to some extent; the original bend straightens and a new one is made nearer the flange. I don't recommend this as a standard route; it is hard work! It is far easier to use spoke washers or different spokes!
cheers
Spoke fatigue & wheel rebuilding
Re: Wheel rebuild - should I replace the spokes?
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~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~
~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~