As much as I want it to be, I don’t think it is. It really, really looks it, they’re clearly deliberately paralleling Sarah Connor/Kyle Reese from the first movie, and that was romantic, so I don’t know how they’re going to stop short of that and no homo it but I just don’t see them going there. Maybe they’ll drop in some kind of familial relationship but they hardly look related.
But yeah, I can’t say 100% it’s not going to go there, but nothing so far in any promotional or review material has at all alluded to anything f/f.