I don’t care for either. I always think of Archie as the comic book character and Ari sounds like a nickname for Arielle, Arianne, Arabella etc. I do like Archer for a boy and you can call him Archie if you like.
Neither. If I had to I'd choose Ari, as it is a full Hebrew name whereas Archie is just a cutesy nickname.For a girl it's okay as a nickname for Ariel.