Indeed it can, but not for the reason it probably looks like. It's not that "alles" is modifying "es". Rather, "es" is such an empty word that it doesn't feel quite right in such a strong subject position. It's got a very different feeling than the English "it" even though they're grammatically equal.
Duolingo wants this sentence to mean "It will change everything", as in (maybe in a film studio) "Wir bekommen morgen ein neues Licht - es wird alles verändern". If you do have the context, this works, but "es" is still slightly uncomfortable out in front.
So what this sentence sounds like instead is that the subject has been moved after the verb, and a meaningless "es" has been inserted to fill the first position. So without context this sentence is equivalent (besides subtleties of style) to the sentence, "Alles wird verändern", that PoTingLim suggests: a translation of "Everything will change".
Given their English sentence (and even in the above context about the light), I'd probably translate it to "Das wird alles verändern". Using "das" instead of "es" makes clear that the neuter pronoun really is a proper subject, not a filler.
Note, though, that none of this applies to other pronouns, even "er" and "sie"! In particular, "Er wird alles verändern" definitely means that er (who- or whatever that actually is) will change everything.