In Western alphabetic languages other than French, English, and Portuguese, not being able to spell the word is virtually identical to not knowing how to say the word.

People who spell words wrong in Spanish are either on the one hand mixing up "k" and "que," "b" and "v," maybe screwing up "c" with "k," "s" and "que" or forgetting the accent placement rules; or on the other hand they've literally heard and said the word incorrectly all their lives.

Also, even the misspellings in Spanish will 99.9% result in perfect pronunciation. The accent rules are just about where you're allowed to omit it, or when you add it to a one-syllable word and it doesn't actually indicate an accent. The error you're most likely to make is to put one in when it is unnecessary.