Honestly, your best bet is to just select the ash skin tone you want, then go to lips and click through them all until you find a color that you think suits it best. It’s also kind of hard when you don’t disclose the exact ash tone you’re using, but it’s also about your personal preference.
When I create ash characters, I only really use either mauve matte or mauve gloss. Everything else is too pink or too peachy against the cool skin.