No magic bullet.
Try a parametric EQ. Start with very narrow Q, gain all up. Sweep the frequency band to find the offensive freq. Then cut gain to notch it out and listen for unpleasant artifacts. If is sucks all the “air” out of the guitar, it’s too much, bring the gain up a bit. I wouldn’t try to remove all the squeaks, it’s a natural part of steel-string performance and will sound weird and unnatural if completely removed.