An alternate ending for Star Wars: Episode III – Revenge of the Sith, preferred by Ewan McGregor and Hayden Christensen, would have had a massive impact on the Star Wars saga. George Lucas has always liked to pretend he had the entire Star Wars saga planned out for decades, but that's something of an exaggeration; while the broad details of the prequels were certainly planned out well before they began production, Lucas was a lot more spontaneous than he claims. This is made abundantly clear by J.W. Rinzler's The Making of Star Wars: Revenge of the Sith, in which the entire production team sometimes seem rather disturbed at how slowly the script is progressing.

https://screenrant.com/revenge-sith-alternate-duel-all-saga-changes/