Assuming you're talking about Unreal - Same principle applies, but you'd multiply your vert color with a new texture map that has that kind of noise pattern. You may need to pass the result through a power node to increase contrast.
I often prefer this approach over multiplying a noise over my vertex color gradient This isn't "better" - its just different The main benefit to me is that it centers the noise around the mid point of your gradient rather than only eating into the higher values and also gives you more contrast. (example in designer but the…