Persia (17, v7.2) : in a nine-years-long war against Russia from 1804 to 1813, with a balanced army roster relying on fast and good skirmishers, light cavalry and fierce mercenaries
Septinsular Republic (10, v.7.1) : ionian islands under France's control from 1807 to 1814/1815, with Balkanic, Greek and French troops;
Mamelukes (15, v.7.1) : Bonaparte's main opponents from 1798 to 1801, with impressive light cavalry, heavy cavalry with plates and shields, and a feudal infantry mostly based on slaves and mercenaries;
Russian partisans and cossacks (14, v.7.1) : the "Maloya Voïna" fought separately from the Russian imperial army, causing up to 70% of the Grande Armée's casualties ; no regular infantry or cavalry, mainly a skirmishing and harassing army.
Click here for more info