I read the script- there's one kiss between her and Ripcord before a battle, and at the end of the movie, they're not standing with their arms around each other or anything like that. They could literally completely ignore S/R in movie 2 and you wouldn't notice. I'm not saying they will, just pointing out how it's written.
Yeah, and Duke, when rescued by G.I. J.O.E., asks what the hell kind of unit they're in, pointing out all the different accents(HD= South African, Breaker= French Tunisian, and Scarlett's Aussie accent). I'm going to take a wild guess that they're not going to have rachel do an accent. Quaid certainly isn't going to do one, I'm sure, even though Hawk is described as British.
BTW- I think Sommers knew he wanted SAid TAghmaoui as Breaker during the writing, given how specific the script is in mentioning where he's from- there just happens to be a French Moroccan who is highly respected who is right for this part of a French Tunisian.