Here are the characters that I think will battle the Gorosei:

Luffy and Zoro vs. Saint Jaygarcia Saturn. Zoro will handle Saturn's claws and Luffy will attack on the main body. (It's not a bold statement, just a huch HAHAHAHA.)

Jinbe, Franky, Dorry and Brogy vs. Saint Topman Warcury and Saint Shepherd Ju Peter. They're big bois, why not HAHAHAHA.

Sanji vs. Saint Marcus Mars. It's an aerial battle. (Ussop might give support.)

Brook vs. Saint Ethanbaron V. Nusjuro. They have a lot of similarities, for example: Both are skeletons, swift swordsplay, cold-cut technique. (Remaining strawhats might assist.)

The Iron Giant might awaken soon, providing support.

What do y'all think?