
Uhm, did you forget by the meaning of someone followed someone even though that person who followed some certain person has a different about something has literally by the meaning they already indirectly called as allies? In this case Jimbei was used to be the enemy of Mugiwara by indirectly, with his subordinate Arlong that was released by roaming free in East Sea, he already made Nami's life miserable and not only that, the current status of Fish Island right now is under Big Mom's territory... IF you can't call that as an enemy I don't what to call it, I'm pretty sure no matter how good it is Jimbei's relationship with Luffy IF the current status of him before he deflected from Big Mom still can be considered as enemy, it's only indirectly form.

There's actually a flaw to what you're thinking there. Jinbei has already agreed to join the Strawhats which makes him the 9th member under Luffy. What Oda was talking about is the 10th member. The enemy member is the next Strawhat after Jinbei ^-^;

If it`s not wrong
Luffy want 10 member
So with luffy it will be 11

According to Oda, the new Member WAS an Enemy, not is still. Jinbei was an enemy as a former member of the Big Mom Crew. And also the Fishmen were enemy to the Strawhats because of namis past, which she is okay with jinbei.

I feel like the last member might be aokiji. Because i think he fits the characteristic. He used to be an enemy of mugiwara crew (marine admiral). He owes garp and he's not like the other marines and fair towards justice. And in the manga he somehow have connection to mugiwara (robin,garp)

Oda was talking about the new nakama after Jinbe

The way Oda Eiichiro-sama is going with the story and what happened on ch. 799 pg. 14 it could very well be Big Mom who is the next new member, along with all her crew of course
We'll just have to wait and see and theorize along the way~
http://www.mangago.zone/read-manga/one_piece/mr/one-piece/799/pg-14/
Whats the price of defeating a yonko? Jinbei joined strawhats but according to oda, the new member is an enemy? Will jinbei die or are we gonna acquire two new members? ( i like jinbei to join too)