Maybe struggle was the wrong word but Franky and Sasaki are going hard, Jimbei is chilling. He wanted to get Luffy to the roof, and it seems the 4fl is WWs.
I only see someone switching Sanji because he wont hit women, see no reason to switch the other two.
We also have still other wildcards, quite a few Numbers are around, Hawkins, Hotei, Fukurokuju.
Drake also has got to fight someone. Sanji will most likely fight a Commander, maybe both him and Drake take on Queen and King.
Why narrow it only to the straw hats. They got allies too. Jack is an executive too and he got downed by mink tribe and the army they had up.