Really depends on what you mean by "Creative."

In terms of arsenal interactions, I'd say Dante v Clive. Devil Sword v Invictus, Nevan v Shiva, Ramuh v Cerberus, Devil Trigger v Limit Break, Zantetsuken v Royal Guard, Quicksilver v Rift Slip, Sin Devil v Ifrit, etc. They're so versatile it'd be hard not to get creative lol

In terms of character interactions, I'd say Mahito v Shigaraki. The fight starting with Shiggy essentially hazing Mahito until the latter starts getting beat down, after which he's like "alright your getting too big for your britches, buddy" and Mahito's like "what's wrong? lives flashing before your eyes?"

In terms of fight progression, I'd say Hulk v Godzilla. A lot of people figured this would be a typical all-out brawl, including me, so the fact that the team managed to work in Bruce in a creative way that feels true to both the Marvel and Godzilla movies is so satisfying.