Meanwhile How I Met Your Mother star Alyson Hannigan was also a guest of the event for Buffy The Vampire Slayer alongside co-star Tom Lenk. A Northern Irish YouTube star has revealed how she has overcome her social anxiety – by transforming herself into a living Manga doll in Japan. Hawaii-born actress Auli’i Cravalho is encouraging Moana fans of all ages to dress up as the Polynesian princess for Halloween amid the ongoing debate about whether or not the costume is a form of cultural appropriation.