You read an email and thought it meant B but later realizes it actually said A. In this scenario, can you say, "I read that email/sentence wrong" or should I use "wrongly"? How would a native speaker describe this? I mistook that email?
Both are acceptable. "Wrong" sounds more natural to me, but "wrongly" is the more formal. If you like you could split the difference and use "incorrectly".
See more at Grammarist.
The correct answer seems to be I read it wrong.
In this sentence wrong would be what grammarians call a flat adverb, with flat meaning:
Flat Gram. Not having an inflectional ending or sign, as a noun used as an adjective, or an adjective as an adverb, without the addition of a formative suffix, or an infinitive without the sign to. Many flat adverbs, as in run fast, buy cheap, are from AS. adverbs in -ë, the loss of this ending having made them like the adjectives. Some having forms in ly, such as exceeding wonderful true, are now archaic.
Webster's Revised Unabridged Dictionary, 1913
Wrong has been categorized in this manner since at least 1828 in the American Dictionary of the English Language by Noah Webster, and probably much longer. Dr. Webster's definitions seem to imply a slight difference between it and wrongly too. Wrong is more of a word of simple error, and wrongly is more of a word for ethical considerations.
WRONG, adverb Not rightly; amiss; morally ill; erroneously.
Ten censure wrong for one that writes amiss. [— Alexander Pope; An Essay on Criticism]
WRONGLY, adverb In a wrong manner; unjustly; amiss. He judges wrongly of my motives.
I have some doubts about this, since the 1913 dictionary's definitions seem to be in disagreement, but the illustrative quotations from each one seem to corroborate this distinction. Webster's 1913 adds this quotation from William Shakespeare's Macbeth for consideration: "And yet wouldst wrongly win."
In consideration of this distinction, it seems senseless to say that you read it wrongly in most circumstances, since there is no inherent evil in merely misreading something. If my hypothesis is correct, the semantic nuance would explain why Google nGrams (archived) does recognize "I read it wrong", yet not the alternative sentence "I read it wrongly", despite the identical syntax.