I don’t quite understand wanting the current cherry MX blue switch to be any lighter at the actuation point: it’s already extremely light.
I wonder if you might be more satisfied with a switch with a higher actuation point, or with a bit of a different force curve. I’d recommend trying blue Alps and blue SMK “monterey” alps-mount switches.
Or alternately, I wonder if there’s a way you could tweak your posture, typing style, or keyboard shape to make typing more comfortable.
With that said though, you could definitely try using a lighter spring with MX blue switches, if you want. You might have to lube them a bit to make sure they return without getting stuck. From that page you linked, you probably want one of the lightest 2 types.