Yeah, not really worth the effort tbh. Also what if you stole 2 mcv of same faction and different subfaction?
The way this could work with negative prerequisite is that for example, a Russian MCV would forbid building a Chinese or Latin War Factory, even if you have the MCV's of those factions. Having for example both a Russian and a Chinese MCV would however allow the player to build a War Factory that can produce the vehicles of both factions. Sticking with Soviet subfactions and War Factories, there would be a total of 7 Soviet War Factories.
Player has...
Russian MCV: can build Russian WF
Latin MCV: can build Latin WF
Chinese MCV: can build Chinese WF
Russian and Chinese MCV: can build a WF that builds both Russian and Chinese vehicles
Russian and Latin MCV: can build a WF that builds both Russian and Latin vehicles
Latin and Chinese MCV: can build a WF that builds both Latin and Chinese vehicles
Russian, Chinese, and Latin MCV: can build a WF that builds vehicles of all 3 subfactions.
7 War Factories that are mutually exclusive thanks to negative prerequisites, and are visually indistinguishable by the player. So it is possible, but IMHO it's crude. I think the ideal solution would be somehow utilizing spies, like if a Russia player infiltrated the ConYard of a Latin player, then the Russian player could build Latin stuff. I don't know if basic prerequisites and stolen thech requirements can implement this, at worst negative prerequisites would have to be utilized, but with clones of the produced units instead of war factories and such, I guess.
Edited by Divine, 21 August 2018 - 06:42 PM.