Guess adverbs are provided in this article. The words listed here are commonly found along with the verb guess in sentences. This reference page helps answer the question what are some adverbs that describe or modify the verb GUESS.
correctly, dimly, easily, exactly
hardly, merely, partly, possibly
probably, randomly, readily, reasonably
rightly, safely, scarcely, shrewdly
simply, surely, usually, vaguely
Hope this word list had the guess adverb you were looking for. In addition to adverbs used with guess, other example verb adverb pairings can be found on this site.
You can help by adding more adverbs in the comments. Thanks.