Following a recent advertisement for Pokemon GO, the official Twitter account announced that Plusle and Minun can now be found together in the world.
— Pokémon GO (@PokemonGoApp) February 10, 2018
In the past, the 2 magnetic mice could only be found in different sides of the world. This was due to their separation between the GBA games, Ruby and Sapphire. Now they finally come together to live in the harmony that they are meant for.
This will make expanding the Pokedex a touch easier. Not to mention all the happy fans that love seeing the 2 Pokemon together. If you know a spot near you that regularly has one of the 2, then might I suggest visiting there again and seeing if the other has appeared. I know I will.