https://store.steampowered.com/bundle/11358/HITMAN_2__Standard_Edition/

This isn't on Steam for whatever reason.

The publisher changed the listing on Steam from a package to a bundle [note that Steam bundles can't be gifted].
SG still points to the giftable package version of the Standard Edition, which is still available as a key from various retaillers.

Since this package version is different from the bundle version currently listed on Steam, Steam won't link to the store listing for the game when following links associated with the package version. You can find the bundle version displayed on the main Hitman 2 page or at the link Captwookie provided. The content between the package and bundle version is identical.

The Standard Edition includes the first season/expansion of content. The Gold Edition includes both seasons/expansions of content. [Roadmap for Season 2 ->]. There is also the Mumbai Pack package, which only has a partial selection of content from the first expansion.

The Hawke's Bay listing is the one associated with the free version of the game. Himmelstein and Mumbai are added within the Mumbai Pack, and the Standard Edition further adds Miami, Santa Fortuna, Whittleton Creek, and Isle of Sgail.

Happy cakeday!

same