Virtual Resolution sampling?

From what I know, it downscales or upscales the resolution to whatever size you want, then rescales it to the original resolution. It may not sound useful, but the game I'm trying to use this on normally uses sprites that are 200% larger than what they normally are supposed to be, with nearest neighbor sampling. The community for this game usually sticks to making all sprites this way, as the game's developer has long moved on, and they never released the source code to accomodate for a smaller resolution. As a result, to prevent clashing and such, usually sprites have to be 200% their original size in order to prevent what the community calls "1x1 pixel clashing". If you've heard of Super Mario Bros. X, or know how its graphical system works, this should sound familiar. I'm trying to figure out a way to have the shader scale the resolution to half its size, then resize the result by 200%. This is already possible with the shader I'm using, but it seems the scaling isn't nearest neighbor.