To start off, people tend to boost their favorite characters over another character despite feats proving otherwise especially after a single power up, like people saying Zoro is stronger than Luffy, Sanji is stronger than Zoro, or that Zoro is leagues above Sanji. So I wanna try and scale their strength.
Right now Luffy is far above the other Straw Hats by a ridiculous amount and he may get even another power-up.
Luffy has a balanced combination of speed and strength as well as Advanced Level of Observation Haki and Armament Haki, the two types of Haki in which Sanji and Zoro respectively specialize in. There’s no doubt that he’s the strongest and it really shouldn’t be up for debate.
Zoro’s power output is insane. Armament Haki is Zoro’s specialty concerning Haki. He has mastered enhancement, hardening, and imbuement, but not the advanced techniques like emission and internal destruction. And after he received Enma in Wano, Zoro’s mastery in Armament Haki is further shown when he forces his Haki back into his arm that was forcefully drained by Enma whereas a normal swordsman would have been drained of all their Haki.
Anyway Zoro couldn’t beat Luffy in a 1v1 fight, I’m not even sure if him and Sanji together could defeat Luffy.
Sanji is incredibly strong but he lacks feats of immense physical strength. Sanji’s speciality is his speed and Observation Haki. Throughout the course of the manga we see several speed feats for Sanji and him being great at evasion and quick reflexes. He even managed to counter’s Katakuri Future Vision despite not having it himself.
The Raid Suit which grants Sanji the ability to fly and strengthen his kicks with propelled boots, and serves as an armor to protect him from attacks, brings Sanji closer to Zoro’s level so much that a fight between them could go either way.