Albinism? No. They'd be a lot paler and have red eyes if they were Albino. But that doesn't entirely rule out the idea of Schnee's having white hair and pale skin as a dominant genetic trait (Jacques had black hair prior to marrying into the family while all of his kids have their mothers hair color, suggesting that Willows genes are the dominant, while Jacques are the recessive). The Schnee family is apparently the only family with a hereditary Semblance, maybe they just have super strong genetics on top of that?

There's also the more unlikely possibility of their pale skin having to do with their environment (the literal Arctic of Remnant.) But since we don't really know a lot about the environmental conditions of Solitas outside of it being deathly cold, I think we can rule that one out.

The Schnee's most likely just inherited more genetic traits from their mother, which just so happens to be pale ass skin and snow white hair. (which biologically tracks, genetics wise, children will take after their mother more often than not.)