'Cause I have nothing better to do, I did a list, based only on its design, of the pokémon that I absolutely loathe and despise.

BUG TYPE
Volbeat
Illumise

DARK TYPE
Pawniard
Bisharp

DRAGON TYPE
Lati@s
Dialga
Palkia
Kyurem (base, Black, White)
Jangmo-o/Hakamo-o/Kommo-o

ELECTRIC TYPE
Magnemite/Magneton/Magnezone
Voltorb/Electrode
Plusle
Minun
Thundurus (base)
Zeraora

FAIRY TYPE
Mime Jr./Mr. Mime
Spritzee/Aromatisse
Swirlix/Slurpuff

FIGHT TYPE
Machop/Machoke/Machamp
Tyrogue/Hitmon (Lee, Chan, Top)
Makuhita/Hariyama
Meditite/Medicham (base, mega)
Timburr/Gurdurr/Conkeldurr
Throh
Sawk
Cobalion
Terrakion
Virizion
Keldeo (both)
Crabominable