If you use CreamAPI and the CreamAPI extensionon the "SteamDB" site, it lets you download ID lists for games. Paste this information into the creamapi.ini file and then copy the DLLs as well as the ini and paste them into the steam game's folder. This works most of the time.
Here's an example for Civ V:Mega Link for Civ V creamapi files
Game Hacks and Cheats
Unlocking free steam DLCs
Submitted by oblit57, 04-06-2018, 08:58 PM, Thread ID: 90924
Thread Closed
04-06-2018, 08:58 PM
#1 RE: Unlocking free steam DLCs 04-06-2018, 09:27 PM #2
04-06-2018, 09:27 PM
#2 RE: Unlocking free steam DLCs 04-06-2018, 09:27 PM #3
04-06-2018, 09:27 PM
#3 RE: Unlocking free steam DLCs 04-06-2018, 09:27 PM #4
04-06-2018, 09:27 PM
#4 RE: Unlocking free steam DLCs 21-06-2018, 12:54 AM #5
21-06-2018, 12:54 AM
#5 RE: Unlocking free steam DLCs 03-07-2018, 11:46 PM #6
03-07-2018, 11:46 PM
#6 RE: Unlocking free steam DLCs 22-08-2018, 05:10 PM #7
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#7 RE: Unlocking free steam DLCs 30-08-2018, 02:24 AM #8
30-08-2018, 02:24 AM
#8 RE: Unlocking free steam DLCs 01-09-2018, 03:24 AM #9
01-09-2018, 03:24 AM
#9 RE: Unlocking free steam DLCs 11-02-2019, 10:02 PM #10
11-02-2019, 10:02 PM
#10 RE: Unlocking free steam DLCs 16-02-2019, 09:07 PM #11
16-02-2019, 09:07 PM
#11 RE: Unlocking free steam DLCs 27-02-2019, 01:22 AM #12 I'mlonely
27-02-2019, 01:22 AM
#12