Both isolating languages and inflected languages can have ways of marking noun classes like masculine nouns, nouns that stand for flat things, etc. Some isolating languages, like Chinese, have classifiers that outnumber the grammatical genders in highly inflected European languages.
I'm betting that classifiers in isolating languages don't trigger anything like agreement rules. Are there other disanalogies between noun classification schemes in isolating languages and noun classification schemes in more inflected languages?