https://wccftech.com/the-witcher-3-the-witcher-1-prologue/

Following the release and the success of The Witcher 3, many have been asking for a remake of the first entry in the series. While CDPR has yet to listen to requests, as far as we know, someone else is giving players a taste of an updated The Witcher 1.

A new The Witcher 3 mod developed by erxv in around 2 months of actual work in collaboration with other talented modders has been released recently, introducing a playable The Witcher 1 prologue to the game.