I believe you may be referring to a or a custom texture pack for Resident Evil 4 Ultimate HD Edition on PC, rather than an official feature or edition of the game. There is no official "Black Box" version from Capcom.
Most texture mods come as .arc or .pack files. Here’s the usual process: Resident Evil 4 Ultimate HD Edition - Black Box
The Ultimate HD Edition, and by extension the Black Box release, came with the full, original voice acting. This is the version that features the iconic, albeit cheesy, dialogue that has become meme legend—from Leon's "Where's everyone going? Bingo?" to the Merchant's insistent "What're ya buyin?" It also included the "Separate Ways" campaign, starring Ada Wong, which was a bonus scenario added in the PS2 and later ports. I believe you may be referring to a
Crucially, the Black Box version included: Here’s the usual process: The Ultimate HD Edition,
It introduced full keyboard and mouse support with customizable key bindings, a feature that was sorely missing in previous PC iterations.
If you love the game, buy the base game on Steam or GOG. Then, download the free RE4 HD Project from the mod authors directly. The "Black Box" convenience is excellent for preservation, but supporting Capcom (even if they ignored the PC port for years) ensures the franchise continues.