SilentStealth71

1. Yes, it does use the streaming method. 2. No, I have not tried modifying it with the replacement method. It's way too time consuming to go through such a tedious process when I'm not having any problems. 3. I haven't had any problems with spawning when using 1899 Firearms. I just don't use Firearms Cosmetics despite it being listed as a requirement because that mod does cause spawning issues.

Yes, you can use 1899 Firearms without Firearms Cosmetics. That's what I run. Just know that some glitching may occur and the custom grips and such will not show up. I overlook these issues as I find 1899 Firearms essential to my play style. I wish this game could handle the textures, but at present it cannot.

I realize that this post is old, but I was also looking for a way to do this and found the answer. You have to edit the associated weapon.ymt file for the gun audio that you want to change. I did this with Maverick Weapons, but this should work with any mod's .ymt file as long as the one you're editing isn't being overridden by another mod. I also downloaded the mod Online Weapons in Story Mode https://www.nexusmods.com/reddeadredemption2/mods/2195 because the .ymt files it has contain the code for the audio for the various weapons. All you need to do is copy the line of code for the audio you want and paste it into the code block for the weapon's audio that you want to change. A tutorial is also provided by the mod author on the mod page.