Sisters, being sisters, always manage to find each other, and the presence of Rebekah - with magic, to boot - is something that Freya picks up on immediately. It doesn't take long for Freya to find her at the bar, as where else would a Mikaelson go, but she does stop when she realizes the clothes she's wearing, and how this might not be the sisterly reunion she had been hoping for.

"Enjoying your evening?" Might as well keep things casual until she figures out what point in the timeline Rebekah has found herself here.