I recently bought Hitman 2 (Gold Edition) on PS4. Before that I already had Hitman 1 (stealbook edition), which I have almost played through (also PS4). Can I now transfer the progress from Part 1 to Part 2?
No. But apparently you get rewards unlocked when a Hitman 1 game is recognized in which a lot of time has been invested:
https://nydus.org/news/107156.html