The laziest is the one they spent literally zero time designing: Missingno. Infact it may even go into negative time, at which point the laziness approaches infinity!
...Okay seriously though, Starly and Diglett. Possibly Ditto as well. Pidove is low on the list too, but it is ultimately more interesting than Starly. And to be fair, I think Pidgey actually looks pretty nice compared to the other 3-stage first form birds.
Voltorb, but I say it is a lazy design, no matter how many details it has.
Come on. How can you people forget Luvdisc. That's the true lazy design. It's like the creators where just rushing to create one last Pokémon to round up the generation or something.
I have just one thing to say.
lazy design =/= boring design
For example, Ditto has a boring design but in no way is it a lazy design. This is because while it does look bland, the concept behind it is very interesting.
Volbeat has a lazy desing but it isn't a boring one. Its a firefly. Fine. What now? Hey atleast it looks cool and a great colour scheme.
Team X-Gen (Black 2)
Karen of the Johto Elite FourStrong Pokémon. Weak Pokémon. That is only the selfish perception of people. Truly skilled trainers should try to win with their favorites