Once upon a time, Jurassic World director Colin Trevorrow was slated to direct and co-write Star Wars: Episode IX, until parting ways with Lucasfilm in September 2017. But though Trevorrow and co-writer Derek Connolly received a story credit in the final film, it seems none of their screenplay was actually used in the making of The Rise of Skywalker.
The Wrap reports (via Slashfilm) that Trevorrow and Connolly’s draft was completely abandoned after director JJ Abrams and co-writer Chris Terrio came on board. Terrio told The Wrap, “We are both a little superstitious about starting with material that might lead us in a direction that’s different than the one we might’ve gone in naturally. So we didn’t begin with the previous script, there may have been certain elements that we used that had been in the original script and we weren’t aware of it.”
Source: IGN.com None of Colin Trevorrow's Original Script Was Used in Episode IX