ATLA AU Chip! He’s the son of two airbenders but was orphaned at a young age and taken in by a group of pirates, most notably cared for by Arlin. Arlin quickly gathered that Chip was the Avatar but with the efforts of the crew, they tried their best to hide it from outsiders as they travelled.
Luck eventually runs out, however, as a villager in a location they passed noticed Chip idly practicing multiple kinds of bending while seemingly having some sort of bending competition with Lizzie, and it was reported to Fire Nation soldiers. The group were attacked in the night by soldiers wanting to capture the Avatar and Chip fled into the wilderness, unsure whether his crew was dead or captured.
Swearing off acting as the Avatar as it had only ever brought him trouble, Chip went into hiding and acted as a nonbender, eventually moving his way up into the Earth Kingdom. He’d stay pretending to have no bending abilities until he encountered a woman getting mugged, panicked and revealed his abilities. The woman in question was Jay, and both of them ended up having to flee, starting his (very reluctant) journey as the Avatar.
