I know it's probably a bit late, but could it be possible to sidestep the Unity asset packaging by adding a bunch of "empty" assets to the game's shipping version, which are then selectively replaced and associated with given modded content? For example: assets1.pak now includes "empty1" through "empty255". The mod manager "hijacks" the asset loading pipeline by injecting the actual modded assets in place of the empties at runtime, associating them with the correct files (.json i assume?) for the new weapons/items. I'm a total compsci beginner, and i know this "solution" is probably MEGA scuffed, but i'd love to get the ball rolling on my own modding project.
