Maybe Mythic Racial Heritage
Mythic Racial Heritage states:
You gain a single racial trait of your choice from the race you picked when you took non-mythic Racial Heritage. That racial trait can’t modify your size or ability scores. You also gain the racial language of the race (if any) if you don’t already know it. For races with multiple racial languages, you gain all of them.
This allows you to get a racial trait from Half-Elf as a human. However, the issue is that Cold-Honed is an Alternate Racial trait, which has the following set of rules (APG pg. 8) (Emphasis mine):
The following race discussions also describe alternate racial traits for each character race. It is important to note that these racial traits are not the same as the trait rules. Those traits are effectively half-feats, intended to tie characters to the specific nations, cultures, regions, and races of the Golarion campaign world. Racial traits, on the other hand, are those racial abilities described at the bottom of each race’s descriptive page. Some races have few racial traits, like half-orcs and humans. Others, like dwarves and gnomes, have many. All of these racial traits represent typical members of the race and the kinds of special abilities they gain from their heritage, whether from biology, racial attitudes, or otherwise.
This chapter also contains a list of alternate class features for each race. [lol, no it doesn't] Some of them play on racial archetypes not reflected in the standard racial traits, like a gnome’s love of languages or tinkering or a halfling’s mastery of thrown items or of slipping through a battlefield under the feet of larger races. In order to choose one of these racial traits, you must exchange one or more of the existing racial traits available to your character. These racial traits replace a character’s normal racial traits; they are not abilities gained in addition to them. In many cases, racial abilities are exchanged on a one-to-one basis; you give up one racial ability from the Core Rulebook to gain one presented in this book. In other cases, you may have to exchange more than one racial trait to take one of these alternate racial traits.
This means that while Cold-Honed is a racial trait, whether the (mythic) feat could simply grant it is up in the air. In it's favor, Cold-Honed is a simple 1-to-1 replacement of a base racial trait, but at the same time, it's still not something that's standard for the race.
Therefore, you would need to ask your GM whether this method works for you. As a GM I'd probably allow it (it is a mythic feat after all), but yours may disagree.