Spoilers for anime ppl and ppl not caught up
Luffy is on a rampage right now trying to find Sanji. Considering that I think it would be extremely anti climactic for the wedding to not actually happen I would assume that Luffy stops his rampage and the wedding happens. Which begs the question how does he stop?
I don't think he is gonna get captured again by Smoothie or otherwise just because he was already captured and then the SH would have to save him and the Vinsmokes during the wedding. On the other hand tho it does give the entire crew motivation to stay rather than Sanji's semi want to save Reiju and his family.
I also don't think that Luffy will find Sanji and feed him and then tell Luffy the situation. Mainly because I feel like Sanji and Luffy aren't gonna meet unless Sanji makes a meal for him (pun intended... doesn't really work cuz of spelling but ¯\_(ツ)_/¯ ) and I don't see that not being a big moment during the wedding when Luffy needs a powerup and sanji cooks him some food or something. I just think its gonna be a big moment during the wedding to add some emotional impact. Another reason is Im not entirely convinced Luffy wouldn't just grab Sanji and haul him off.
What I actually think is gonna happen is (drum roll... and no one cares anyway) is that Chopper/Carrot are gonna find Sanji and Sanji will tell them he can't leave cuz he has to save his family, cuz Sanji is too nice to leave them behind. Then Chopper goes and finds Nami and Jinbei who are doing who knows what (following Luffy) and stashes them in the mirror world. Then Luffy gets to Smoothie and in his weakened state gets wrecked. Then the mirror world people save Luffy and run into the mirror world. I could see all of them fighting smoothie cuz Jinbei is there but that could be saved for the wedding. So then all the SH- Sanji are in the mirror world and can plan whats gonna happen during the wedding. The important part tho is that they get Luffy in the mirror world without being seen cause then that gets rid of their advantage. Plus they would not be able to tell Sanji the plan. On top of it all everyone gets to take a break and recuperate, obviously Luffy won't eat but he can rest. Then they break into the wedding and save all the Vinsmokes. Maybe there is a scene where Judge is grateful to Snaji and becomes good or maybe they just save Reiju cuz who cares about the others.
anyway thats all I got. Feel free to disagree or hate on it but thats what I think is gonna happen. Even tho all of these are probs wrong cuz Oda.