Yup, or since Modest Charizard doesn't need its attack, a 31 / x / 31 / 31 / 31 / 31 is also considered flawless.
"Unfortunately, IVs are completely random for each of your Pokémon's stats. That means you may get good IVs for your Attack and Defense, but bad IVs for the other four stats.
Since IVs range from 0 to 31, you have a 1 in 32 chance of getting a perfect IV for one stat. But getting perfect IVs for all six stats is nearly impossible. You only have a one in 1,073,741,824 chance of doing that."
While you do have way better chances breeding flawless than capturing flawless, your chances are still very low. This is where RNG abuse comes in, so we have way better chances of capturing or hatching flawless (and, maybe shiny).