And with Zack? There was that Marlene scene after all and Aeriths feelings for Cloud were a major plot point in rebirth wether they were romantic or not.
So do you think that maybe her feelings will be brought up with Zack instead?
Nevertheless, in Rebirth, Aerith tells Cloud straight up she still loves Zack. No ambiguity or beating around the bush, a straight "Do you still love Zack?" - "Yes."
One cannot suggest otherwise, even if one wants to say she has feelings for Cloud, because she was not separated from Zack by anything other than circumstance. They never had the same resolution that Rebirth has given us for CA, vis, the "now I know where we stand" date in Sector 5, nor did they ever have the same issues that exist up to that point for CA - such as Cloud being stuck in his SOLDIER fantasy persona during their brief encounter, and ultimately, his love for Tifa. These and more are major hurdles that the ship never fully manages to clear, but no such narrative struggles exist for ZA.
This much is for certain, she still has feelings for Zack - she admits it and her actions prove it - and he very clearly has feelings for her. SE did not bring him back for this thread to be left unresolved and they did not decide to end things in Advent Children Complete without recognizing the need for Zack/Aerith to have a reunion, ahead of their depicted togetherness in death.