I would associate positive connotation to strategic family therapy, and reframing more to structural family therapy, but essentially meaning the same thing. I did find this below in helping to understand the two better in their slightly different ways...

\"Therapists use positive connotation to respect both the family's fear of change and their request for change. They interpret the behavior of each member of the family positively, as having an underlying benevolent motivation (Boscolo et al., 1987). A common positive connotation is reframing a child's problematic behavior as a way to keep the parents together and reframing the parents' arguments about how to handle this behavior as a way to show their dedication to the family and each other. Perhaps the most important outcome of positive connotation is the effect it has on the therapist, enabling the therapist to view members of the system less judgmentally and with greater hope. P 99 Gehart Gehart, D. R. (2018).Mastering competencies in family therapy: A practical approach to theory and clinical case documentation(3rd ed.). Boston, MA: Cengage\" and then...

\"A reframe takes a situation and lifts it out of its old context (old set of rules) and places it in a new context (new set of rules) that defines it equally well. However, this new context offers an alternative understanding, or new meaning, to which new and different responses are logical and thus possible. Pp 300\"

https://www.coursesidekick.com/psychology/1053453#:~:text=Reframing%20allows%20the%20therapist%20to,behavior%20for%20the%20family%20structure

Difference between Positive Connotation and reframing