Good day everyone
I may have found a way to workaround the hassle of installing mods for GRB, according to my limited modding experience with this game
For example, you choose a simple cosmetic replacement mod for your game, downloaded it, install it exactly as instructed, but somehow it crashed midway through the loading screen. My solution to this problem is to delete the GRB document files inside C:\Users\(your user name)\Documents\My Games. There should be a file called "Ghost Recon Breakpoint". Delete it and it "may" solve the problem (as it did work for me, I had installed quite a bit of cos mods)
Also, this trick did work (for me) with a gun replacement mod without the need of the pre sept patch, which the creator did point out that I need that patch for it to work (the "Improved AK-47 Assault" mod)
I haven't tried it all out with mods that need pre sept patch, so I just put my recent findings here for u guys to figure out on ur own. Goodluck!