When i was playing fallout 4 while my friend was watching me during "Share Play" Allowing him to watch or take command on my controller, i thought of an idea where he could take command of my companion and play with me sorta like a multiplayer game, i know fallout 4 is not multiplayer based but itd be cool to roam the wastelands killing raiders and super mutants with a friend that knows what their doing. Rather than having a companion that dies over and over again. With this idea the players could maybe trade? and such, but the companions/2Player inventory stays the same when he/she leaves. making it a whole lot better of a game. If skyrim has this type of idea why not fallout except more simpler.?
Edit: The 2 player could load his characters save as a companion, allowing him to keep any loot he finds instead of benefiting one player