Scourge aasimar (Volo's Guide to Monsters, p. 105) have the Radiant Consumption trait, part of which states:

Starting at 3rd level, you can use your action to unleash the divine energy within yourself, causing a searing light to radiate from you, pour out of your eyes and mouth, and threaten to char you.

Your transformation lasts for 1 minute or until you end it as a bonus action. During it, you shed bright light in a 10-foot radius and dim light for an additional 10 feet[.]

Can a scourge aasimar's Radiant Consumption trait dispel magical darkness, or even encroach upon it?

I'm thinking not, but it's a racial ability, so it doesn't have a spell level.