I assumed not, but I saw
言い知れぬ甘美なもの
Translated as "something inexpressibly sweet", as if 言い知れぬ modified 甘美な. Is it just a quirk of translation and both the adjective 言い知れぬ and 形容動詞 modify もの (that is, lit: something inexpressible and sweet), or does 言い知れぬ modify 形容動詞 here somehow?
言い知れぬ is an expression that is used like an adjective, but is actually a negative verb. Basically, it's an archaic way of saying 言い知れない. In this case, don't think of 言い知れぬ as modifying the na-adjective. Think of it as modifying the noun which has already been modified by the na-adjective. The "sweetness" isn't what's indescribable; the "sweet thing" is.
