For example: “Your level English” (Your level = adjunct)? Does it have the same meaning as “English of your level”?
At the very least you’d need to hyphenate, like this: your-level English. This would arguably be understood by most native speakers to mean English of your level. But I doubt any native speaker would actually use such a construction under normal circumstances; it’s just not natural. It is true that there are similar constructions that are fully idiomatic, such as higher-level math, next-level advice, etc. But is just a fact of life that your normally can’t enter into such constructions.
CGEL would refer to both higher-level and next-level as an attributive modifier realized by a nominal. The your-level modifier would be a nonce formation similar to a no-frills airline and an all-or-nothing approach. Nonce here means that ‘forms of these types are not
systematically admissible in this construction’ (CGEL, p. 444). In these cases, the obstacle is that they contain determiners (genitives like your function as determiners), and determiners are not systematically admisible as constituents of attributive modifiers. They are only admissible as particular nonce formations—sometimes. Not in your case, however. I don’t know a deep reason why that is; we just don’t normally use your (or other possessive pronouns such as my, his, her, our, and their) in such constructions, and unfortunately that’s all I can say about it.