Both but this is apparent from the mod description
GTEFGHA:[..]would clean it[..]
You are looking for the non-reshade version of this LINK
DownbeatPower85:[..]volumetric clouds[..]
We are using reshade I seem to remember McFly modding through reshade recently so look for those kind of mods maybe he has already done it I dont see why It wouldn't be possible.
I personally think its way more complicated than it would worth in visual quality improvement, but that is just my opinion I think the needed resources (depth buffer and access to a proper version of shading) are there so knock yourself out if you manage to port McFlys implementation the guys at the "Show off your ride" forum would probably build you a pedestal