So, I think Luffy will do fairly well against Imu until he runs out of Gear 5
Zoro and Sanji unlock CoC and start to win against Sommers and Killingham
Once Luffy runs out of Gear 5, Shamrock/Garling and possibly other God's Knights show up
Shuri reveals Imu's weaknesses to help
Hybrid Loki vs Imu, Zoro and Sanji vs Garling and Shamrock
Then top tiers like Shanks/Mihawk who sensed Imu start to arrive.
Since Zunesha arrived at the end of Onigashima for Joy Boy, I think Zunesha will come here sensing Imu's descent.
My big question: what presence does Blackbeard send to Elbaph? Kuzan? Himself?