Our gardens are a continent apart but the generic classes you state above indicate that you are asking about "grasses" first, and "legumes" second? I have successfully grown the Clouded Sulphur to maturity on the Crowfoot Fox Sedge (Carex crus-corvi).
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The "just-vacated" Chrysalis with the stretching butterfly.
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The only legume that I have grown is one called Showy Tick Trefoil. It blooms bountifully with multi-colored typical legume blossoms and the seed pods are made up of extremely adhesive "beggar's ticks". It grows to fill a 4' high plant that is wider than it is tall. So far it has acted more as a pollen plant than as a host plant, though it is highly touted as a host plant.

Showy Tick Trefoil (Desdemoniun canadense).
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Another legume that has been moderately successful in my garden has been Wild Senna (Cassia hebecarpa)

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Bob

In California, the Clouded Sulphur larval host plants include Astragalus crassicarpus, Medicago sativa (alfalfa), Melilotus officinalis (yellow sweet clover), Trifolium repens (white clover), T. pratense (red clover), and Vicia americana (Vetch) per my search of the Internet.

I love your photo of the flowers of Senna hebecarpa, Bob. I have never found Clouded Sulphur on mine - only Sleepy Orange and Cloudless Sulphurs, but I don't see too many of the Clouded Sulphur in my garden. My plant died last year, so I need to replace it, altho I do grow Xmas Cassia (bicapsularis) for both the Sleepy Orange and Cloudless Sulphurs that they use as an LFP as well. I just love the S. hebecarpa when in full bloom - gorgeous native.

Is that the butterfly you are trying to attract? I don't see a specific mention of it, but I could be going blind...

Susan

Thanks for the recommendations Bob. Unfortunately, neither of those are native to the west coast. I did find the Lupinus species which appears to be native in California. So I will look more into those as well as the ones Susan mentioned.

I've since decided not to plant a Gramineae (Poaceae). With the limited space I have I had to cut something. In my area it's a host plant for 7 species of skippers which isn't really a focus.