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According to Dr. Karl, yes it can.

https://www.abc.net.au/science/k2/homework/s95605.htm#:~:text=The%20hair%20can‘t%20actually,base%20of%20the%20hair%20follicle.

Hair gets its colour from a chemical called melanin, which is pumped in by cells at the base of the hair follicle. As your hair goes grey, these cells at the base stop making melanin. So some hairs will be their normal colour, but some (the ones without melanin) will be completely white. So here’s a great truth - there’s no such colour as grey hair. Grey hair is dark hairs, with the newer white hairs mixed in.

So how can somebody’s hair turn white overnight? Easy, they first have grey hair (which is actually the mix of dark hair and white hair) - and then all the dark hair falls out over a few days.

This could be caused by a disease called alopecia areata , where your hair, for no apparent reason, simply falls out. Unlike common balding, alopecia areata is just as likely to happen in women as in men.

So if you’ve got grey hair, and those few remaining dark ones bail out, bingo - instant white hair! It can’t happen overnight, but it can happen...

Can Fear or Stress Change Your Hair Color?
Any extraordinary emotion can change the color of your hair, but not instantly. Your psychological state has a significant impact on the hormones that can affect the amount of melanin deposited in each strand of hair, but the effect of emotion takes a long time to see. The hair you see on your head emerged from its follicle a long time ago. So, graying or any other color change is a gradual process, occurring over the course of several months or years.

https://www.thoughtco.com/can-hair-turn-white-overnight-604317