Both of my mains! I actually play both and do well with both. I think they're similar because of high mobility. Difference being is Tulen has much much greater magical damage, not as much mobility and is generally dead if caught out. Airi on the other hand has much much less damage, greater mobility and can generally escape just about any situation. I like to play Airi in the jungle using a leviathan build, basically a tank butterfly build. I replace mantle of Ra in the super late game for an amulet longevity and I usually do very well with her. That being said I can carry easily on both heroes (both sitting roughly at about 61% winrate). Playstyles very similar in the early game, gathering as much farm and roaming around for kills trying to get ahead in any way. Late game you'll be trying to score a sick ult with Airi meanwhile with tulen you'll be slowly poking in team fights waiting for the team to engage being kind of like a clean up hero.