Atomic Heart does not require a separate download link for a Spanish language pack because Spanish audio and subtitles are included in the base game. You can activate them directly through the in-game settings. How to Change the Language to Spanish
In-Game (Subtitles/Text): Go to Options > Gameplay > Language to select your preferred text language. atomic heart spanish language pack link
If the automatic DLC download fails, you can force the download via the Steam Console (Advanced method): Atomic Heart does not require a separate download
to download a Spanish language pack. Because the game launched with nine supported voice-over languages—including Spanish—the files are already included in your game installation. atomic heart spanish language pack link