Yellow vein kratom is not a distinct strain of kratom from red, white, or green kratom.
Instead, raw white kratom strains are processed in a certain method to produce yellow vein kratom. The color of the leaves changes from white to yellow as a result of this way of drying and processing them, as well as the plant's impact profile.
In terms of impact, yellow kratom strains are identical to green Malay kratom. They're euphoric, strong, and have a really clean "pick-me-up" vibe to them. They also have a relatively long lifespan. As a nootropic or mood-booster, many people favor yellow vein variations to white vein antecedents.