This mod reskins and remodels every unit in the game, to look more like the Great Northern War that occured in North-East Europe in the 18th century. It was between the Swedish Empire and the Anit-Swede Coalition, mainly led by Russia. This mod will work perfectly fine on regular Napoleonic Wars servers, as it's just a reskin.
To install the patch, just extract all the file into the Napoleonic Wars folder. Make sure that you have the latest version of the mod installed.