'Revisionist' is a word often used as a pejorative. But are there revisionist works of history (books, studies) that single-handedly changed the consensus on a topic in a dramatic manner?
The work of a historian is to revise, to take new concepts, perceptions, theoretical understandings and apply them to the past in order to create new knowledge and understanding. Rinse and repeat. All good history is revisionist history, as we are not recorders of the past (that is an archivist), but its interpretors.
As for you specific question I would say David Blight's Race and Reunion and Caroline Janney's response in Remembering the Civil War help to set off a recent flowering of young scholarship in American memory studies.
Many of these take on new perspectives and attempt to give voice to the historically voiceless, which is the primary goal of good revisionist history.
One major piece of work in economic history was Robert Fogel's Railroads and American Economic Growth: Essays in Econometric History.
This was the major work of the "cliometric revolution". Fogel set out to estimate the contribution of railways to US GDP in the 19th century and came to the conclusion that it was trivial:
"the level of per capita income achieved by January 1, 1890 would have been reached by March 31, 1890, if railroads had never been invented."
Fogel also showed evidence that no other industry is likely to have been more important than railways. This was a major change in economic history, turning people's attention away from particular industries as a driver of industrialisation.
To reach this conclusion Fogel made important methodological contributions, creating an explicit and quantifiable counter-factual (an expansion of canals, shipping and roads) using a formal economic model, and introducing the concept of "social savings": the difference in social costs between the real and the counterfactual worlds. Fogel also was cautious, when he had to make assumptions he made ones that were biased in favour of railways being more important than they were.
Reportedly Fogel's results initially surprised himself, when he set out on his project he expected to find that railways were very important.
So there you are, a radical revision to economic history not just in its findings but in its methodology.
Source
Review by Lance Davis of Railroads and American Economic Growth: Essays in Econometric History, https://eh.net/book_reviews/railroads-and-american-economic-growth-essays-in-econometric-history/