If I understand your question, you're looking to obscure some of the walnut grain. Stains alone (even gel stains), though they may contain pigments, won't do that.
To get that effect, you'll have to do one of two things:
A) Add a small amount of paint to your stain. To avoid adherence issues, you should test the compatiblity, and always add water base paint to waterbase stain, and oil base paint to oil base stain. You should not add more than 10% paint to the mix, and the paint color should be close to the color of the wood, when just stain is applied. It doesn't hurt to also add about 5-10% thinner.
B) Stain first, let stain dry, then seal surfaces with Sealcoat. When Sealcoat dries, make a mix of 60% paint & 40% thinner (same color as described above). Spray or brush this on, and then evaluate before it dries. If you don't like it, wipe off with rag dipped in thinner, before it dries. You can also play around with this, by removing or adding to certain areas. If you like, let dry, then apply Sealcoat, then your finish of choice.
Of the 2 methods, I prefer the first. I also recommend you test the mix and make samples.
Bob "Boardman" Borders