So Jesse’s first transformation wasn’t a bloody or terribly timed thing. They were super careful not to be near any towns, or in a publicly viewed place on the full moon. Hanzo stayed with him through the whole thing, which helped with Jesse being able to remember who he really was. (It also helped that McCree had valuable knowledge on werewolves from his hunting, and prepared for what to expect. Just in case Hanzo needed to pull the trigger, so it were) It was fuzzy the first few times, but even if he wasn’t sure who this blue fella was, he felt safe with him.