I have specific pokemon i dislike but I always hate spammers.
1.Bronzor omfg D/P/P like everyone you see can confuse u or put you to sleep its freaking annoying. Plus its abilities come on Heatproof or Levitate. Come on...... that leaves it one weakness. Though I love Steel types i cant stand Bronzor.
2. I dont hate FEAR pokemon simply beacuse it proves the other person cant win by skill, and they wont survive to hits(lol someoene tried that on my lvl 100 Lucario with Extrememespeed, now that was funny^^
3. Double team spammers, nuff said
4. I hate Wobbofett. While I will admit it is good much as I hate to see it, I cant stand when I know I cant OHKO it and I know it will choose the right Counter type move to use.
5. STAB earthquake pokemon(lol even If i own some myself) They freaking always slaughter my team of like all STeel Types and like one or 2 other types(One of which is probably Dragon and the other Absol, who always travels with me)