Does it matter what Pokemon you battle after you max out their EVs?

Question

I was leveling a Pokemon in attack and defense. I maxed out its EVs very quickly. After battles, it would gain 2 in attack after some battles and 3 in attack after others. Do I still need to worry about what Pokemon I'm fighting to get the stats I want?

Answer 1

No, you do not need to worry. Once you have your EVs maxed out (all 510 of them), then you will not gain EVs from defeated/captured Pokémon.

Source: Experience