[FREE][STEAM] Soundtracks you can activate in Steam (legal, without base game, etc.)

This is a list I've made myself of all currently soundtracks, audiobooks, drama CDs and sound stuff that you can add for free and legally to your Steam library. You shouldn't even need the base game to add them (read below for a caveat).

I started with this thread about the same subject: https://www.steamgifts.com/discussion/XCks6/free-music-in-steam-can-add-without-base-game
So thanks to everyone there for their contribution. That thread hasn't been updated in more than one year, so I think it's better to make a new post than to use necromancy.

I used it as a start, getting more than half of this list from there; then removed the things no longer available, used some searches in SteamDB and Steam Store to find more, and since now these products have the nice blue button "add to library" in the store page, I skipped the SteamDB step (but it's in the instructions nonetheless).

The list is not prone to errors. For example, I might have been able to activate one soundtrack because I already had the base game, and it's really a bother to check for those. It's also a bother to check which ones that I already had could be activated by others without the base game, so yes, there might be stuff not there, or stuff there that shouldn't be. All things you need to know are in the text as caveats, instructions and comments, and then the list, currently 266, of the links of all these free products you can add.

Everything is in this PasteLink link. Feel free to share the link anywhere you want. Last update: 23-Oct-2024.
https://pastelink.net/d12v8s82

You can also report stuff (in the way explained in the list) in this thread, I'll try to update the list, but I might not be available or active. Thank you.