>>54393261It's hard to say which ones are the best, but I could go over a few of the major ones briefly.
Pokemon Special (Adventures) - One of the longest and now-largest (not a high bar for Pokemanga) running series. Battle manga with an emphasis on character drama and adapting fine details of each game.
Electric Tale of Pikachu - Adaptation of the Indigo League/Orange Islands anime; has great art if you don't mind the curvy figures of character designs (it was drawn by a shameless hentai artist).
Magical Pokémon Journey - Romance shoujo manga. Very cute to say the least.
Pocket Monsters - Slapstick comedy manga. Very juvenile humour and very loosely based off the game universe. Actual longest running manga (although it only runs online now, instead of in the magazines).