Ainz Ooal Gown would be very interesting. His complex personality, with his mix of pride as an Overlord and his insecurities hidden beneath, would create a lot of depth. In the Naruto world, his reactions to the different values and cultures would be fascinating. For example, how would he deal with the concept of chakra compared to his own magic? And how would he interact with the ninjas who have such different combat styles and moral codes from his undead minions?
Naruto himself could be a great focus. His unwavering belief in friendship and his never - give - up attitude could be put to the test when facing Ainz. He might initially try to befriend Ainz, seeing the good in everyone. But as he discovers Ainz's more sinister plans, he has to find a way to overcome the overwhelming power of this new foe. His journey in understanding Ainz's world and magic would also be an interesting aspect to explore.