The saved settings within my mod menu (enhanced trainer) were causing the crash, resetting it solved the problem which was caused by spawning multiplayer weapons in the game while LSPDFR was loaded.
I can run LSPDFR fine with Scripthook V.NET and RAGE, but as soon as I install Scripthook V, LSPDFR crashes when loading in (can run RAGE fine without it loading LSPDFR fine, though). My only other mods are the Enhanced Native Trainer.
My .net framework is also up to date at 4.8
I can run the game if I delete scripthook and all the other related features. It sucks as I can only run Ragehook and LSPDFR with no trainer which makes things very inconvenient.