That photo is amazing! I love it! This is expensive, but I've heard an Expodisc works great to set white balance. All you need to do is hold a larger one in front of the lens and set the white balance once. Buying one for each lens would be prohibitive. You could also use a good gray card, like WhiBal.
ExpoDisc 2.0 - Professional White Balance Filter - ExpoImaging, Inc. https://luminous-landscape.com/whibal-review/