BMW Group currently sells the most plug-in electric cars in Europe.
However, if we include plug-in hybrids, there is no competition for BMW Group (BMW & MINI brands) and Volkswagen Group (Audi, Porsche, Volkswagen). Those two already sold between 40,000 to 45,000 units each through the end of August in 2018, including less than 15,000 BEVs. BMW is slightly above Volkswagen, but the BEV/PHEV proportions seem close to the same.
As you can see in the graph below, big progress was achieved by Hyundai Group (Hyundai & Kia) too, which seems to be in fourth place.
Far, far behind is hybrid-tycoon Toyota, which plays the game these days by suggesting it has no interest in plug-ins.