Re: "Road to Giverny" (Claude Monet)
Perhaps a look at values by comparing would help. To get a softer look, the values need to have subtle changes as they move from light to dark, with softer and more blended edges. That being said, in this painting, Monet was using strong lines, but do notice how the values change from snow to trees to sky.
I found a comment that "he used a palette of Ultramarine or Cobalt Blue, Cadmium Yellow, Vermilion and Alizarin Crimson for reds, Viridian and Emerald Green for greens, Cobalt Violet, and Lead White."
He would mix the colors so he would have cool and warm families of each.
I hope this helps, all artists like practicing paintings of the masters they admire, it so enriches the artistic journey. Cheers